The blunt-headed or blue-headed wrasse, a fish of the species Thalassoma amblycephalum or Thalassoma bifasciatum.(noun)
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Use "bluehead" in a sentence
"The creek is home to a pair of native species of fish, the bluehead and flannel-mouthed suckers, and possibly the round-tailed chub, although the presence of the latter never has been confirmed, White said."
"The Zuni bluehead sucker, a small fish found only in three remote canyons in New Mexico, is considered an endangered species by that state and is a candidate for listing by the federal government as endangered, and this April, 17 spawned at the Albuquerque Biological Park's refugium producing about 40 larval fish."