качнуть

Russian

Possibly кача́ть (kačátʹ) +‎ -ну́ть (-nútʹ) (or derived the other way around).

качну́ть • (kačnútʹ) pf (imperfective кача́ть)

to rock, to swing, to shake, to wobble; to dandle (once)
качну́ть колыбе́ль ― kačnútʹ kolybélʹ ― to rock the cradle (once)

качну́ть голово́й ― kačnútʹ golovój ― to shake one's head (once)
to pump (once)
(transitive or impersonal) to toss, to roll, to pitch (once)
ло́дку качну́ло ― lódku kačnúlo ― the boat tossed / rolled (once)
(colloquial) to lift up, to chair (to toss someone up, like a group of fans their champion)
(colloquial) to train/pump muscle (once)

Conjugation of качну́ть (class 3b perfective transitive)

Note: For declension of participles, see their entries. Adverbial participles are indeclinable.
perfective aspect
infinitive	качну́ть kačnútʹ
participles	present tense	past tense
active	—	качну́вший kačnúvšij
passive	—	ка́чнутый káčnutyj
adverbial	—	качну́в kačnúv, качну́вши kačnúvši
	present tense	future tense
1st singular (я)	—	качну́ kačnú
2nd singular (ты)	—	качнёшь kačnjóšʹ
3rd singular (он/она́/оно́)	—	качнёт kačnjót
1st plural (мы)	—	качнём kačnjóm
2nd plural (вы)	—	качнёте kačnjóte
3rd plural (они́)	—	качну́т kačnút
imperative	singular	plural
	качни́ kační	качни́те kačníte
past tense	singular	plural (мы/вы/они́)
masculine (я/ты/он)	качну́л kačnúl	качну́ли kačnúli
feminine (я/ты/она́)	качну́ла kačnúla
neuter (оно́)	качну́ло kačnúlo