flower head

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A dense, compact cluster of small flowers that appear to be a single flower, as of a dandelion or clover.
• noun A very dense grouping of flower buds, as in broccoli and cauliflower.

from The Century Dictionary.

• noun In botany, a form of inflorescence consisting of a dense cluster of florets sessile upon the shortened summit of the axis, as in the Compositæ.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun botany A compact cluster of florets having the appearance of a single flower (as in the daisy family)

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun a shortened compact cluster of flowers so arranged that the whole gives the effect of a single flower as in clover or members of the family Compositae