alf a mo, n. — Green’s Dictionary of Slang

alf a mo n.

also arf a mo

[Cockney pron. of SE half + mo n.¹]

1. a cigarette, esp. when it proves hard to keep alight.

1984

Partridge DSUE (8th edn) 25/1: 1914–15.

2. (Aus.) a small moustache.

1919		W.H. Downing Digger Dialects 7: ’alf-a-mo — a small moustache.
1924		(con. WWI) A.G. Pretty Gloss. of Sl. [...] in the A.I.F. 1921–1924 (rev. t/s) n.p.: alf-a-mo [...] A small moustache, which was also frequently referred to as a cricket match (eleven a side).