dive / dīv/ • v. (past dived or dove / dōv/ ; past part. dived) [intr.] 1. plunge head first into water: she walked to the deep end, then she dived in | he dived off the bridge for a bet. ∎  move quickly or suddenly in a specified direction: a bullet passed close to his head, and he dived for cover | [as adj.] (diving) he attempted a diving catch. ∎  (of an aircraft or bird) plunge steeply downward through the air: the aircraft dove for the ground to avoid the attack. ∎  (dive into) occupy oneself suddenly and enthusiastically with (a meal or an engrossing subject or activity): dive into a barbecued beef burrito. ∎ fig. (of prices or profits) drop suddenly: profits before tax dived by 61 percent. ∎ inf. put one's hand quickly into something, esp. a pocket or purse, in order to find something: she dived into her bag and extracted a card. ∎  Soccer , Ice Hockey (of a player) deliberately fall when challenged in order to deceive the referee into awarding a foul.2. swim under water using breathing equipment: he had been diving in the area to test equipment. ∎  (of a fish, a submarine, or a vessel used for underwater exploration) go to a deeper level in water: the fish dive down to about 1,400 feet and then swim southwest.• n. 1. an act of diving, in particular: ∎  a plunge head first into water, esp. from a diving board in a way prescribed for competition: he hit the sea in a shallow dive | a high dive. ∎  an instance of swimming or exploring under water with breathing equipment: divers should have a good intake of fluid before each dive. ∎  an act of going deeper under water by a fish, submarine, or diving vessel: pilot whales can go to 600 meters in a dive lasting 18 minutes. ∎  a steep descent by an aircraft or bird: the jumbo jet went into a dive. See also nosedive. ∎  a sudden movement in a specified direction: she made a dive for the fridge to quench her raging thirst. ∎ fig. a sudden and significant fall in prices or profits: an 11 percent dive in profits. ∎  Soccer , Ice Hockey a deliberate fall by a player, intended to deceive the referee into awarding a foul.2. inf. a disreputable nightclub or bar: he got into a fight in some dive.PHRASES: dive in help oneself to food.take a dive Boxing pretend to be knocked out. ∎  (of prices, hopes, fortunes, etc.) fall suddenly: profits could take a dive as easily as they could soar | her reputation took a dive from which it has not recovered.

dive vb. trans. OE.; intr. XIII. OE. dȳfan wk. trans. dip, submerge = ON. dȳfa :- *dūƀjan, f. Gmc. *dūƀ-; OE. dūfan intr. did not survive, being replaced by the wk. form; belongs to the Gmc. series *dauƀ- *deuƀ- *duƀ-, parallel to *daup- *deup- *dup- DEEP, DIP.
Hence as sb. XVII; in the U.S. sense of ‘low resort for drinking, etc.’ from the sense of the vb. ‘dart out of sight’.