Green’s Dictionary of Slang

noser n.

1. [mid–late 19C] a bloody nose [nose v. (3b)].

2. [mid–late 19C] (also nose-ender) a blow on the nose [nose v. (3b)].

3. [mid-19C+] (US Und.) an informer [nose n. (1)].

4. (US) an interfering person.