[1] : The Collaborative International Dictionary of English v.0.48

umbellate \um"bellate\, umbellated \um"bella`ted\, a. nl.
   umbellatus. bot.
   bearing umbels; pertaining to an umbel; umbel-like; as,
   umbellate plants or flowers.
   1913 webster

[2] : WordNet (r) 2.0

umbellate
     adj 1: bearing or consisting of or resembling umbels syn: umbellar
     2: resembling an umbel in form syn: umbel-like
see also:
umbellar umbel-like 

Umbellate >> U Words
Umbellate, definition of term: Umbellate
umbellate_pag1.html