hedge (n.) Look up hedge at Dictionary.com
Old English hecg "hedge," originally any fence, living or artificial, from West Germanic *hagjo (cognates: Middle Dutch hegge, Dutch heg, Old High German hegga, German Hecke "hedge"), from PIE root *kagh- "to catch, seize; wickerwork, fence" (cognates: Latin caulae "a sheepfold, enclosure," Gaulish caio "circumvallation," Welsh cae "fence, hedge"). Related to Old English haga "enclosure, hedge" (see haw (n.)).

Figurative sense of "boundary, barrier" is from mid-14c. As hedges were "often used by vagabonds as places of shelter or resort" [Century Dictionary], the word, compounded, "notes something mean, vile, of the lowest class" [Johnson], from contemptuous attributive sense of "plying one's trade under a hedge" (hedge-priest, hedge-lawyer, hedge-wench, etc.), a usage attested from 1530s. The noun in the betting sense is from 1736 (see hedge (v.)).
hedge (v.) Look up hedge at Dictionary.com
late 14c., "make a hedge," also "surround with a barricade or palisade;" from hedge (n.). The intransitive sense of "dodge, evade, avoid committing oneself" is first recorded 1590s, on the notion of hiding as if in a hedge. That of "insure oneself against loss," as in a bet, by playing something on the other side is from 1670s, originally with in; probably from an earlier use of hedge in meaning "secure (a debt) by including it in a larger one which has better security" (1610s). Related: Hedged; hedging. The noun in the wagering sense is from 1736.