Synonyms for Significant:

adj.

all (adjective)
important.
important (adjective)
serious, high, central, big, considerable, noteworthy, vital.
important, critical (adjective)
material, noteworthy, notable, consequential, meaningful, vital, substantial, big, considerable.
indicative (adjective)
evidential.
life-and-death (adjective)
earthshaking.
meaningful (adjective)
indicative, purposeful, explanatory, definitive, relevant, vital, communicative, topical, explicit, denotational, meaningful, notable, descriptive.
oracular (adjective)
portentous.
representative (adjective)
symbolic.
substantial (adjective)
material, tangible, solid, actual, physical, palpable, real, immanent, meaningful, firm, bodily, substantive, united, appreciable, considerable, sturdy, important, substantial.
telling, meaningful (adjective)
expressive, meaning, suggestive, serious, indicative, pregnant, eloquent, symbolic, important, momentous.

n.

huge, king-size, wide, enormous, great, vast, immense, high. express, show, well-defined, unambiguous, representational, telling, eloquent, illocutionary, expressive, symbolic. suggestive. historic, consequential. significant (noun)
important, operative, key, evidential, world-shaking, evidentiary, remarkable, monumental, probative, noteworthy, portentous, pregnant, meaningful, earthshaking, epochal, profound, large, epoch-making, momentous, substantial, world-shattering, fundamental, considerable, meaning, prodigious, head, big.

Other synonyms:

symbolic, illocutionary, unambiguous. consequential, representational, historic. eloquent. meaning. crucial
telling.
eloquent
expressive.
remarkable
remarkable.

Usage examples for significant

  1. " Let her have her own way," she whispered with a significant glance toward Zoie. – Baby Mine by Margaret Mayo
  2. It was also significant that she did not notice that the room, which had no stove in it, was very cold. – A Damaged Reputation by Harold Bindloss
  3. Carley, I'd like your idea of the most significant thing in Glenn's letter. – The Call of the Canyon by Zane Grey