HEDGEHOG n.
A form of dredging machine. Knight. Hedgehog caterpillar (Zoöl.), the hairy larvæ of several species of bombycid moths, as of the Isabella moth. It curls up like a hedgehog when disturbed. See Woolly bear, and Isabella moth. -- Hedgehog fish (Zoöl.), any spinose plectognath fish, esp. of the genus Diodon; the porcupin…
HEPTANE n.
Any one of several isometric hydrocarbons, C7H16, of the paraffin series (nine are possible, four are known); -- so called because the molecule has seven carbon atoms. Specifically, a colorless liquid, found as a constituent of petroleum, in the tar oil of cannel coal, etc.