- 1[intransitive, transitive] to move or make someone or something move suddenly forward and/or downward + adv./prep. She lost her balance and plunged 100 feet to her death. The train left the track and plunged down the embankment. plunge somebody/something + adv./prep. The earthquake plunged entire towns over the edge of the cliffs.
- 2[intransitive] (of prices, temperatures, etc.) to decrease suddenly and quickly synonym plummet Stock markets plunged at the news of the coup. This year profits plunged by 40%.
- 3[intransitive] + adv./prep. (of a road, surface, etc.) to slope down steeply The track plunged down into the valley.
- 4[intransitive] to move up and down suddenly and violently The horse plunged and reared. (figurative) His heart plunged (= because of a strong emotion). Phrasal Verbsplunge inplunge something inplunge into somethingplunge somebody/something into something
NAmE//plʌndʒ//Verb Forms present simple I / you / we / they plunge
he / she / it plunges
past simple plunged
-ing form plunging