Green’s Dictionary of Slang

nosh n.

[nosh v.]

1. [1910s] a delicatessen.

2. [1940s+] food, esp. a snack.

3. in attrib. use of sense 1.

4. [1990s+] an act of fellatio.

In compounds

nosh-up (n.)

[1950s+] a feast; a meal.