I. de ‧ but 1 /ˈdeɪbjuː, ˈdeb- $ deɪˈbjuː, dɪ-/ BrE AmE noun [countable]
[ Date: 1700-1800 ; Language: French ; Origin: début , from débuter 'to begin' , from but 'starting point' ]
the first public appearance of an entertainer, sports player etc or of something new and important
sb’s debut
He made his Major League debut as shortstop.
film/acting/directorial etc debut
His Broadway debut was ‘The Scarlet Pimpernel’.
debut album/CD/single etc
Their debut album was recorded in 1991.
debut match/performance etc
He scored in his debut match for the club.
II. debut 2 BrE AmE verb
1 . [intransitive] to appear in public or become available for the first time:
The show will debut next Monday at 8.00 pm.
2 . [transitive] to introduce a product to the public for the first time ⇨ release SYN launch :
Ralph Lauren debuted his autumn collection in Paris last week.