"channel in earth made by running water," 1650s, possibly a variant of Middle English golet "water channel" (see gullet). Gully-washer, American English colloquial for "heavy rainstorm," attested by 1887.
Entries linking to gully
gullet n.
"passage from the mouth of an animal to the stomach," c. 1300 (as a surname), from Old French golet "neck (of a bottle); gutter; bay, creek," diminutive of gole "throat, neck" (Modern French gueule), from Latin gula "throat," also "appetite," which is related to gluttire "to gulp down, devour," glutto "a glutton." De Vaan writes, "We seem to be dealing with an onomatopoeic formation of the form *gul- / *glu-." Compare Old English ceole "throat;" Old Church Slavonic glutu "gullet," Russian glot "draught, gulp;" Old Irish gelim "I devour."