Word Study
capitulum
CIDE DICTIONARY
capitulum, n. [L., a small head.].
A thick head of flowers on a very short axis, as a clover top, or a dandelion; a composite flower. A capitulum may be either globular or flat. Gray. [1913 Webster]
OXFORD DICTIONARY
capitulum, n. (pl. capitula) Bot. an inflorescence with flowers clustered together like a head, as in the daisy family.
Etymology
L, dimin. of caput head
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