boutonniere
A boutonnière (French for buttonhole) is a flower or bud traditionally worn on the lapel buttonhole of a man's jacket on special occasions.
Nowadays it is not gender-specific, but if the flower is not explicitly on the lapel (i.e. post #5881928) use corsage instead.
h4.See also
* corsage
* lapel pin
* Boutonnière (Wikipedia)
Aliases: none