Definition of tuxedo noun from the Oxford Advanced Learner's Dictionary

tuxedo

noun
tʌkˈsiːdəʊ
 
; tʌkˈsiːdoʊ
 
plural tuxedos (also informal tux
tʌks
 
; tʌks
 
)
(especially North American English)
 
1 (British English also dinner suit) a black or white jacket and trousers/pants, worn with a bow tie at formal occasions in the evening2 (British English also dinner jacket) a black or white jacket worn with a bow tie at formal occasions in the evening From Tuxedo Park in New York, where it was first worn.