On grammatical class:

bai'i
mekso string operator (ternary): find-and-replace; in string/text/word/sequence X1 formally replace X2 (ordered tuple of terms to be replaced) with X3 (ordered tuple of terms to be respectively substituted)
be'ei'oi
ternary mekso operator: x1th Bergelson multiplicative interval with exponents bounded from above by function x2 and with sequence of shifts x3, where exponents belong to set x4
bei'u'i
unary mekso operator: nth Bernoulli number Bn of the second kind (B1 = +1/2 = >0).
boi'ai
unary mekso operator: immediately convert number into a single digit.
ca'ei'a
Unary mekso operator: unit vector/normalization of the argument (vector) X.
ca'o'e
mekso 4-nary operator: spherical harmonics on colatitudinal/polar angle a and azimuthal/longitudinal angle b of unassociated order c and associated order d.
ca'oi
binary operator: complex number from argument and phase, (r, \phi) \mapsto r ei \phi
ci'ai'u
unary mex operator: n-set; maps a nonnegative integer 'a' to the set \1, \dots ,a\ (the intersection of the set of all natural numbers with the closed ordered interval [1,a] such that a geq 1).
ci'au'i
mensonge at-most-3-ary operator: integer lattice ball; the set of all points belonging to the intersection of Zn with the closure of the ball that is centered on X1 and has radius X2 in metric X3, where Z is the set of all integers and where, for any set A and non-negative integer n, An is the set of all n-tuples such that each coordinate/entry/term belongs to A
ci'o'au
mekso operator (binary): projection function; the Bth term/entry ("element") of tuple A
cu'au'ei
mekso binary/unary operator: multinomial coefficient/binomial coefficient/choose
da'a'au
mekso operatory: prime mark append
dei'au'o
mekso binary operator: Lambert product-log W function; W(a, b)
di'ei'o'au
mathematical ternary operator: Dirichlet convolution (a×b)(c)
du'a'e
mekso n-ary ordered operator: structure creator/ordered tuple, 'endow'; the structure formed by underlying set X1 (as) endowed with element, order, quoted operator, etc. X2, X3, ...
du'a'o
mekso binary operator: extract substructure/underlying set/endowing operator; the substructure (general sense; includes just operator, order, set, etc.) of X1 (structure; explicitly given by {du'a'e}) which is formed by collecting the ith entries of that {du'a'e}-tuple in order together into their own {du'a'e}-tuple (or by extracting them naked into the ambient environment if X2 is a singleton) for all i in set X2
du'ei
mekso binary operator: left-handed vectorial cross product (ordered input), -a \times b = b \times a (if using right-hand convention - notice the negative sign/operator or order).
fa'ai
mathematical ordered n-ary operator: (pointwise) functional left composition; X1 \circ X.
fa'au
mathematical unary operator: map notation
fe'ei
binary mekso operator: divided by (fraction): a/(b...)
fei'i
mekso variable arity (at most ternary) operator: number of prime divisors of number A, counting with or without multiplicity according to the value B (1 or 0 respectively), in structure C
ga'ai
unary mekso operator: Lorentz-Einstein gamma factor +1/((1-(|X|2)) for input X.
gau'a
mekso (no-more-than-4-ary) operator: Gaussian function f(x, a, b, c) = c e-((x-a).
gu'au'i
mekso operator, variable arity - algebraic structure order of X1; OR: order of/(size of) period of element X1 in algebraic structure X2 under operator/of type X3
je'e'e
mekso operator: assoviated Legendre polynomial in a with unassociated order b and associated order c
ji'e'ai
mekso unary operator: determinant, det(A)
ji'i'u
mekso at-most-4-ary operator: a rounding function; ordered input list is (x,n,m,t) and the output is b(-t) × round(bt × x), with rounding preference n and where the fractional part of bt × x being 1/2 causes the function to map bt × x to the nearest integer of form 2Z+m, for base b and an integer Z determined by context
joi'i
mekso string operator (n-ary): formal left-concatenation; X1+X, where Xi is a string/word/text
ku'au'a
mekso (n+1)-ary operator: q-analog converter - the ath analog of b (quoted operator) applied to operands c, d, ...
ma'au
Binary mekso operator: uniform probability A(X2)u(X for input (X1,X where X1 is a number and X2 is a set or space. (See notes for details).
mai'u
unary mekso operator: signum function
ma'o'e
mathematical operator: vague/elliptical/general/generic operator
me'ei'o
mekso n-ary operator: interleave sequences
mu'ai'au
mathematical/logical/mekso ternary operator: μ (mu) operator: outputs the most extreme extended-natural number that satisfies relationship/predicate A, where extremeness is bounded by B and of a version determined by C; error output is -1
mu'au
unary mekso operator: measure of the complement; 1 - x1.
nei'au
unary mekso operator: (-1)x
no'au'au
mathematical/mekso binary operator: the zero/identity-element/(primitive (-))constant operator; outputs the identity-element of structure A (contextless default: the additive group of integers) regardless of the input value of B (except blank or ill-defined values)
pau'a'u
mekso operator: part of number/projection (one sense); the X2 part of X1
pau'ei
mekso operator: power set - produces the set of all subsets of set A that are of (any) size (that is) b [a nonnegative integer or transfinite/infinite number]
pei'e'a
at-most-3-ary mekso operator: "integer exponent" for X1 divided by X2 in algebraic structure X3
pi'au'e
mekso ternary operator: extract digit from number; X2nd macrodigit/term of number/tuple X1 when X1 is expressed in base/basis X3.
pi'ei
mathematical/mekso binary operator: vector or function inner product over a field; the inner product of A and B over field C
pi'ei'au
mathematical ternary operator: not-greater-prime-counting function
pi'ei'oi
mathematical ternary operator: prime-generating function
po'i'oi
mekso at-most-3-ary operator: convert to polynomial; X1 (ordered list of algebraic structure (probably field) elements) forms the (ordered list of) coefficients of a polynomial/Laurent-like series with respect to indeterminate X2 under ordering rule X3 (default for finite list: the first entry is the coefficient of the highest-degree term and each subsequent entry is the next lesser-degree coefficient via counting by ones and wherein the last entry is the constant term)
ra'i'e
ternary mekso/mathematical operator: radical; for input (x,y,z), it outputs the largest y-th-power-free product of prime divisors of x in structure (ring) z.
rai'i
mekso (2 or 3)-ary operator: maximum/minimum/extreme element; ordered list of extreme elements of the set underlying ordered set/structure X1 in direction X2 of list length X3 (default: 1)
sau'i
mekso n-ary operator: reciprocal of the sum of the reciprocal of each of X1, X2, ..., Xn (for any natural number n); 1/((1/X1) + (1/X.
se'i'a'o
unary mathematical operator: identity function id(a) = a
si'oi'e
n-ary mekso operator: Logistical growth, sigmoid function; \bigg( \frac(X2)(1+e^(-X.
tai'i'e
mekso unary operator: Kleene star - X1*
te'au'u
mekso ternary operator: Knuth up-arrow notation: a \uparrow \dots \uparrow b of order/with c-2 arrows ("\uparrow") initially, evaluated from right to left; the cth hyperoperator on a by b.
te'i'ai
6-ary mekso/mathematical operator: Heaviside function/step/Theta function of a, of order b, in structure c, using distribution d, within approximated limit e, with value f_b at 0
tei'au
4-ary mekso operator: Taylor expansion/polynomial term; for ordered input (X1, X, output is the X3th Taylor polynomial term of at-least-X3-smooth function X2 which was expanded around point X4 and which is evaluated at point X1, namely (1/(X3!)) × (D^X.
te'o'a
unary mekso operator: natural exponentiation operator exp, where exp(a) = ea \forall a.
to'ei'au
binary mathematical operator: Jordan totient function Ja(b)
vau'i
mekso n-ary operator: reciprocal of the successive ordered-difference of the reciprocal of each of x1, x; id est output is ((\dots ((x1^-1 - x
vei'u
binary mekso operator: mod(ulus)/remainder; X1 % X2, \,\,\, X1 (mod(X2)).
vi'oi'au
mekso unary operator: the set of all fixed points of function a
vo'au'u
quaternary mathematical operator: (left) convolution (a★b)(c) in structure d
xa'ai
mekso operator: the bth branch of the (possibly multivalued) function a
xo'ei
unary mekso operator: produces a string of n consecutive "xo'e"'s, treated as digits (concatenated into a single string of digits)
xo'e'o'ei
At-most-unary mekso operator: like {xo'ei} but for selma'o XOhEhOhE, rather than just PA
za'ei
mekso binary operator: right-handed vectorial cross product (ordered input), a×b
zi'a'o
mathematical operator: the empty/null [one sense]/trivial [one sense]/blank operator
cia'o'e
mekso 4-nary operator: spherical harmonics on colatitudinal/polar angle a and azimuthal/longitudinal angle b of unassociated order c and associated order d.
xua'ai
mekso operator: the bth branch of the (possibly multivalued) function a
cu'a
unary mathematical operator: absolute value/norm |a|.
de'o
binary mathematical operator: logarithm; [log/ln a to base b]; default base 10 or e.
fa'i
unary mathematical operator: reciprocal; multiplicative inverse; [1/a].
fe'a
binary mathematical operator: nth root of; inverse power [a to the 1/b power].
fe'i
n-ary mathematical operator: divided by; division operator; [(((a / b) / c) / ...)].
fu'u
n-ary mathematical operator: elliptical/unspecified mathematical expression (mex) operator.
ge'a
mathematical operator: null mathematical expression (mex) operator (used in >2-ary ops).
gei
trinary mathematical operator: order of magnitude/value/base; [b * (c to the a power)].
ju'u
binary mathematical operator: number base; [a interpreted in the base b].
ne'o
unary mathematical operator: factorial; a!.
pa'i
binary mathematical operator: ratio; [the ratio of a to b].
pi'a
n-ary mathematical operator: operands are vectors to be treated as matrix rows.
pi'i
n-ary mathematical operator: times; multiplication operator; [(((a * b) * c) * ...)].
re'a
unary mathematical operator: matrix transpose/dual; A*.
ri'o
trinary mathematical operator: [integral of a with respect to b over range c].
sa'i
n-ary mathematical operator: operands are vectors to be treated as matrix columns.
sa'o
trinary mathematical operator: [derivative of a with respect to b of degree c].
si'i
trinary mathematical operator: [sigma summation of a using variable b over range c].
su'i
n-ary mathematical operator: plus; addition operator; [(((a + b) + c) + ...)].
te'a
binary mathematical operator: to the power; exponential; [a to the b power].
va'a
unary mathematical operator: additive inverse; [- a].
vu'u
n-ary mathematical operator: minus; subtraction operator; [(((a - b) - c) - ...)].
su'ifa'uvu'u
mekso operator: plus or minus with order important, (((a±b)±c)±...±z)
su'ijavu'u
mekso operator: plus or minus, (((a±b)±c)±...±z)
bai'ei
unary mathematical operator: successor/augment/increment (by one), succ(a) = a++ = a+1
cu'ai
binary mathematical operator: vector norm/magnitude of vector a in structure (normed vector space) b
de'au'u
mekso ternary operator: positive super-logarithm; the super-logarithm (inverse operator of hyper-operator with respect to "height" of power tower) of a with base b and of order c-2.
fe'au'u
mekso ternary operator: positive super-root; the bth super-root (inverse operator of hyper-operator with respect to base) of a of order c-2.
gu'ai
binary operator: left group action g.x
jau'au
unary mathematical operator: length/number of components/terms of/in object/array/formal string/sequence/word/text in some alphabet/base/basis which includes each digit; number of digits/components/entries
ka'au
mekso unary operator: cardinality (#, | |)
ne'oi
unary operator: primorial a#
pau'oi
unary mathematical operator: predecessor/diminish/decrement (by one), \operatornamepred(a) = a-- = a-1
ru'ei
n-ary operator: n-ary magma/group/ring operator a*b = ab`

In definition:

cmavrvu'u
x1 is the selma'o "VUhU".

In notes:

kau'ai
Microdigit-spanning endianness binary-toggle.
kau'au
Macrodigit-spanning endianness binary-toggle.
ma'oi
selma'o quote; quotes a word (a cmavo) and uses it to name a selma'o.
ma'oi'e
Like "ma'oi" but outputs the officially-designated/canonical sub-selma'o (if any) to which the immediately following and quoted word (cmavo) belongs, otherwise outputting the whole relevant selma'o in fashion equivalent to "ma'oi".
noi'a'u
PA nonrestrictive/incidental relative clause; attaches to a PA number/numeral/digit with the ke'a referring to that PA number/numeral/digit.
poi'a'u
PA restrictive relative clause; attaches to a PA number/numeral/digit with the ke'a referring to that PA number/numeral/digit.
te'au
iterated Cartesian product with self: A × A × ... × A, n times.
xau'e
symbol string to number/variable
enfa
x1 abstractly pertains to an exponential/root/logarithmic relationship between the elements of x2 (ordered pair) which are related via concrete relationship x3.
mekseia
x1 is a part of Lojban text representing rule 'mex-operator' according to the first edition of the book 'The Complete Lojban Language'.