Green’s Dictionary of Slang

gob n.2

also gog
[the term appears mid-16C as SE; it gradually declined in status over the next 300 years]

1. [mid-16C+] a lump or clot of some slimy substance.

2. [early 17C; 19C+] a lump, a mouthful.

3. [late 19C+] (UK Und.) a theft carried out by a thief who spits on a man’s coat, alerts him to the problem, then robs him while pretending to ‘help’ him clean up.

4. [late 19C+] one who is typified by their spitting.

(a) (US, also gobshite) any sailor.

(b) a sailor’s hat.

5. [20C+] a lump; thus gobby adj., lumpy.

6. [1910s] (UK public school) someone who makes one feel sick.

7. [1970s] spit.

8. see gobshite n. (2)

In compounds

gob-gobbler (n.) [gobbler n.2 ]

[1980s+] (US gay) a gay man who prefers sailors as partners.

gobhawk (n.)

see separate entry.