bullhead

American  

[bool-hed] / ˈbʊlˌhɛd /

noun

1. any of several North American, freshwater catfishes of the genus Ictalurus, having a rounded or truncate caudal fin.

2. any of several other fishes, as the freshwater sculpins of the genus Cottus, especially those species having a hornlike spine on each side of the head.

3. an obstinate or stupid person.

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bullhead British  

/ ˈbʊlˌhɛd /

noun

1. any of various small northern mainly marine scorpaenoid fishes of the family Cottidae that have a large head covered with bony plates and spines

2. any freshwater North American catfish of the genus Ameiurus (or Ictalurus ), having a large head bearing several long barbels

3. a scorpion fish, Scorpaena guttata , of North American Pacific coastal waters

4. informal a stupidly stubborn or unintelligent person

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Etymology

Origin of bullhead

An Americanism dating back to 1665–75; bull ¹ + head