Definition of "yellowhead"

yellowhead

noun
plural yellowheads
1. A yellowhead butterflyfish (Chaetodon xanthocephalus).
2. A yellowheaded jawfish (Opistognathus aurifrons).
3. A plant of some species of genus Inula of the daisy family.
4. A plant in genus Trichoptilium, in the daisy family.
5. A plant of species Zanthoxylum flavum, related to citrus.
6. (informal) A pimple or pustule without a blackhead.
  Quotations
  A pustule is the typical pus spot or yellowhead.
  2007, Tim Mitchell, Alison Dudley, Acne: The At Your Fingertips Guide, page 5
7. A mohua (Mohoua ochrocephala), a bird of New Zealand.