In the land of the frogs, 'chapeau' translates to 'hat.' To say 'Chapeau!' is to metaphorically take one's hat off to one's peer(s).
'Chapeau!' can have meanings as varied as 'Hello!'; 'Yes'; and 'Well done!' Either
way, it must only be used in the presence of those in whom you hold high esteem; in other
words, only in the presence of
true scholars and not that of the so-called 'yobs.'
STUDENT: '... and that it why the Weimar Republic collapsed.'
TEACHER: 'Chapeau! What a thesis!'
OR...
FRIEND 1: 'Salutations
Mr. X! How are you
today?'
FRIEND 2: 'Ah, yes, what a pleasure it is to encounter you again. *COUGHS* Chapeau!'