Definitions
1.nounAny fish in the Platycephalidae family.
2.noun(plural only "flatheads") A type of screw or bolt designed to fit in a countersink so that it sits flush with a surface.
3.noun(plural only "flatheads") A type of engine that has the valves placed in the engine block beside the piston, instead of in the cylinder head, as in an overhead valve engine.
4.nounA large freshwater catfish native to North America, Pylodictis olivaris.