Capitate is a term used to describe certain insect antennae. Capitate antennae have a prominent club or knob at their ends. The term capitate derives from the Latin caput, meaning head.
Capitate is a morphological form of antennae found in some insect groups, most notably in butterflies (Lepidoptera).
Capitate is just one of many morphological forms of insect antennae. See also:
Source: Borror and DeLong's Introduction to the Study of Insects, 7th Edition, by Charles A. Triplehorn and Norman F. Johnson