Antonyms of adj everyday

3 senses of everyday

Sense 1
everyday, mundane, quotidian, routine, unremarkable, workaday -- (found in the ordinary course of events; "a placid everyday scene"; "it was a routine day"; "there's nothing quite like a real...train conductor to add color to a quotidian commute"- Anita Diamant)

INDIRECT (VIA ordinary) -> extraordinary -- (beyond what is ordinary or usual; highly unusual or exceptional or remarkable; "extraordinary authority"; "an extraordinary achievement"; "her extraordinary beauty"; "enjoyed extraordinary popularity"; "an extraordinary capacity for work"; "an extraordinary session of the legislature")

Sense 2
casual, everyday, daily -- (appropriate for ordinary or routine occasions; "casual clothes"; "everyday clothes")

INDIRECT (VIA informal) -> formal -- (being in accord with established forms and conventions and requirements (as e.g. of formal dress); "pay one's formal respects"; "formal dress"; "a formal ball"; "the requirement was only formal and often ignored"; "a formal education")

Sense 3
everyday -- (commonplace and ordinary; "the familiar everyday world")

INDIRECT (VIA familiar) -> strange, unusual -- (being definitely out of the ordinary and unexpected; slightly odd or even a bit weird; "a strange exaltation that was indefinable"; "a strange fantastical mind"; "what a strange sense of humor she has")

Similarity of adj everyday

3 senses of everyday

Sense 1
everyday, mundane, quotidian, routine, unremarkable, workaday -- (found in the ordinary course of events; "a placid everyday scene"; "it was a routine day"; "there's nothing quite like a real...train conductor to add color to a quotidian commute"- Anita Diamant)
       => ordinary (vs. extraordinary) -- (not exceptional in any way especially in quality or ability or size or degree; "ordinary everyday objects"; "ordinary decency"; "an ordinary day"; "an ordinary wine")

Sense 2
casual, everyday, daily -- (appropriate for ordinary or routine occasions; "casual clothes"; "everyday clothes")
       => informal (vs. formal) -- (not formal; "conservative people unaccustomed to informal dress"; "an informal free-and-easy manner"; "an informal gathering of friends")

Sense 3
everyday -- (commonplace and ordinary; "the familiar everyday world")
       => familiar (vs. strange) -- (within normal everyday experience; common and ordinary; not strange; "familiar ordinary objects found in every home"; "a familiar everyday scene"; "a familiar excuse"; "a day like any other filled with familiar duties and experiences")