sinxa -sinx-sni- gismu

x1 is a sign/symbol/signal representing/referring/signifying/meaning x2 to observer x3.

Also: x1 signifies x2; (adjective:) x1 is significant/meaningful/of import; signal an action (= sniti'i), connotation (= se sibyti'isni, sibyti'ismu). See also lerfu, tcita, barna, mifra, smuni.

In notes:

almapamla
x1 is a plant symbolizing the idea of love, to x2.
ambigu'o
x1 is ambiguous, open to interpretations x2 (plural of property of x1)
barna
x1(s) is a/are mark(s)/spot(s) on x2 of material x3.
blazone
x1 (object, text) is a blazon, verbal or written description of the coat of arms x2
ceisni
x1=s1 is an idol/a sign/symbol representing god/demon/property x2=s2 to observer x3=s3
dasysni
s1 is a badge/insignia worn by d1 signifying s2 to s3.
dimsni
s1 is an omen predicting fate s2 to person(s) s3
esku
x1 is the text for x2 (concept) according to x3 in language x4; x1 is how x3 would word x2 in language x4; x3 would say x1 when they would want to communicate x2 in language x4; x1 is text(ual) / a quote (meaningful) in language x4.
jecysni
x1=s1 is the national symbol representing country/state/polity x2=s2=j1 to observer x3=s3
lerfu
x1 (la'e zo BY/word-bu) is a letter/digit/symbol in alphabet/character-set x2 representing x3.
metfo
x1 (bridi) is a metaphor/figurative expression having literal meaning x2 to observer x3
mifra
x1 is encoded/cipher text of plain-text x2 by code/coding system x3; x1 is in code; x3 is a code.
nalra'a
x1 is irrelevant/unrelated to x2; x1 is arbitrary in relation to x2 [object of comparison; context or referent].
rinsita
x1 is a heart symbol / is heart-shaped ( ♥ )
selsni
x1 is the meaning of symbol x2 as observed by x3
selvensni
si1 is a brand/trademark/maker's mark/logo representing product/service v2=si2 recognized by observer/audience/demographic si3
slogane
x1 (text, entity) is a slogan of x2 (entity)
smuni
x1 is a meaning/interpretation of x2 recognized/seen/accepted by x3.
smuvanbi
v1 is the context of meaning v2=s1 of event/action/object s2 recognized by s3.
snicmaci
c1 is an algebra of type/describing c2
snicne
x1 is a variable taking value x2 under conditions x3.
sniga'i
g1 reassigns s1 from s2=g2 to s2=g3.
snigau
x1 assigns symbol/variable x2 to value/referent x3 for observer x4.
snisku
x1 expresses/transmits symbol/meaningful expression x2 for audience x3 by doing x4 (ternary relation between x1, x2 and x3)
snitatu
x1 is a tattoo
tapsni
si1 is a track of st1 treading on surface st2 using limb st3
tcita
x1 is a label/tag of x2 showing information x3.
tidysni
x1 is a bookmark.
ty'i (exp!)
at a point on time axis
uensni
x1 is text meaning x2 in language x3
vinpa
x1 is a deliberately placed sign meaning x2 to x3 (x2 being relevant to x3's situation when perceiving x1)
zgika'usni
s1 is a music note (symbol).