capitulum
Concise Oxford English Dictionary © 2008 Oxford University Press:
capitulum /kəˈpɪtjʊləm/
▶noun (pl. capitula /-lə/) Anatomy & Biology a compact head of a structure, in particular a dense flat cluster of small flowers or florets.
– origin C18: from L., dimin. of caput ‘head’.
'capitulum' also found in these Oxford entries:

