1. Important in effect or meaning
   "a significant change in tax laws"; "a significant change in the Constitution"; "a significant contribution"; "significant details"; "statistically significant"
   - important 
2. Fairly large
   - substantial 
3. Too closely correlated to be attributed to chance and therefore indicating a systematic relation
   "the interaction effect is significant at the .01 level"; "no significant difference was found" 
4. Rich in significance or implication
   - meaning, pregnant

See also: considerable, earthshaking, earth-shattering, epochal, epoch-making, evidential, evidentiary, fundamental, important, large, meaningful, momentous, monumental, noteworthy, of import, operative, portentous, probative, probatory, prodigious, profound, remarkable, significance, significantly, signify, world-shaking, world-shattering

Antonym: insignificant, nonsignificant

Encyclopedia: Significant

• header
• headfast
• headfirst
• headfish
• headful
• headgear
• headhunt
• headhunter
• headily
• headiness
• heading
• headlamp
• headland
• headless
• headlight
• headlike
• headline
• headliner
• headlinese
• headlock
• headlong
• headman
• headmaster
• headmastership
• headmistress