panra gismu

x1 parallels x2 differing only in property x3 (ka; jo'u/fa'u term) by standard/geometry x4.

Also: x1 is parallel to x2, x3 is the only difference between x1 and x2 (= terpanra for reordered places); x1 and x2 are alike/similar/congruent. A parallel involves extreme close similarity/correspondence across the entirety of the things being compared, generally involving multiple properties, with focus placed on one or a small number of differences. See also pa'a, mintu, simsa, girzu, vrici.

In definition:

pa'a
panra modal, 1st place (parallel; shared property) similarly; in addition to ...
sepa'a (comp!)
panra modal, 2nd place similarly; similar to ...
tepa'a (comp!)
panra modal, 3rd place (property) contrastingly; contrasting in property ...
vepa'a (comp!)
panra modal, 4nd place (standard/geometry) similarly; similar by standard ...

In notes:

girzu
x1 is group/cluster/team showing common property (ka) x2 due to set x3 linked by relations x4.
mintu
x1 is the same/identical thing as x2 by standard x3; (x1 and x2 interchangeable).
simsa
x1 is similar/parallel to x2 in property/quantity x3 (ka/ni); x1 looks/appears like x2.
vrici
x1 (set/mass/ind.) is miscellaneous/various/assorted in property x2 (ka).
si'a
discursive: similarly.
pacpanra
x1 is an evil counterpart to x2 by moral standard x3, in contrast to x2 having property x4.
panrykle
x1=k1 (mass/si'o) is an equivalence class within/is a substructure of x2 (mathematical structure/object/category/set endowed with operations and properties) with defining characteristic/property/for similarity/under equivalence relation x3=p3, with representative member x4=p1=p2, in geometry/by standard/under paradigm x5=p4
panryzilbri
x1=b2=p3 is a (predicate) equivalence relationship/similarity/parallel with/between/among arguments (sequence(s)/set(s)) x2=b3=p1=p2, partitioning (with only empty intersection) set/structure x3=p4; elements of x2 are mutually similar in property x1 within structure x3; x3 is partitioned by x1 into equivalence classes (including) x2;
smisi'u
The members of x1=simx1 (set) resemble one another in property x2=simx2.
terpanryziltolju'i
x1=j2=p3 (ka; jo'u/fa'u term) is the minor difference in/between x2=p2 and x3=p1 that is to be ignored, their similarity being by standard/in geometry x4; x2 is the same as/similar to/parallels x3 in standard/geometry x4 up to/modulo/except for/ignoring unimportant difference x1;
tolpanra
x1 contrasts-with/is-distinguished-from/is-set-apart-from x2 in property/aspect x3
kukru
x1 is orthogonal/perpendicular/right/at right angle/rectified/square/normal to x2, where they (are projected to) intersect orthogonally at locus/on set x3, otherwise being utterly distinct (and not even on the same axis/scale) in sense x4
modju
x1 (li; number) is congruent to x2 (li; number; see description for canonical/traditional/contextless default usage) modulo x3 (li; number); \frac(x1 - x is an integer.
anra
x1 parallels x2, differing only in that x1, and not x2 has the property x3, by standard x4
fraktali
x1 is a fractal with properties x2
tsekane
x1 (linear manifold, vector, etc.) is/lies secant to x2 (object, surface, curve, manifold, etc.) passing through or toward points/loci x3 (set of intersected points), by standard/definition/in system x4.
zo'anjo
x1 (linear manifold, vector, etc.) is/lies tangent to x2 (object, surface, curve, manifold, etc.) at point/locus x3, by standard/definition/in system x4.