slightly 29 synonyms and 3 antonyms for slightly, ranked by how commonly they're used. Adv — To a small degree or extent. Synonyms for slightly a bit a little a little bit a mite a smidgen a smidgeon a tad a touch a trifle barely closely faintly hardly imperceptibly just kinda kinda sorta kind of low-key marginally modestly mildly nearly only just scarcely somewhat sorta sorta kinda sort of Antonyms for slightly almost mostly very ← Back to the full definition of slightly