Green’s Dictionary of Slang

yuck v.

(US campus/teen) to vomit.

1963		AS XXXVIII. 301: [Newfoundland.] Yuck, to vomit.
1981		PADS LXVIII 54: [Newfoundland.] To vomit, yuck.
2001		S. King Dreamcatcher 618: Deke began to make muffled yurking sounds behind his hand.

In phrases

yuck up (v.)

1. to vomit.

1994		D. Lehane A Drink Before the War 112: All the nerves in my skull were freshly exposed [. . .], and I stood up and just made the bathroom before I yakked up the Glenlivet.
1999		Indep. Information 31 July–6 Aug. 25: Look at them chortle over the duff scatalogical jokes, and yuck it up.
1999		Observer Mag. 12 Sept. 94: It was even in the newspaper that day, me yucking my guts up.

2. see yuk up under yuk v.