Moreton (bay), n. — Green’s Dictionary of Slang

Moreton (bay) n.

also Morton

[rhy. sl.; Moreton Bay fig(s); ult. Moreton Bay, from 1824–39 the penal settlement sited at the mouth of the Brisbane River, Queensland]

1. (Aus. Und.) cigarettes.

1950

S.J. Baker in Sun. Herald (Sydney) 8 June 9/5: Only two of Detective Doyle's [rhyming slang] examples seem to be home-grown. One is ‘Moreton Bay figs,’ for cigarettes or ‘cigs’.

2. (Aus. Und.) an informer [= fizgig n.²].

1972		Dodson & Saczek Dict. of Cockney Rhy. Sl.
2002		Pete’s Aussie Sl. Home Page 🌐 Moreton Bay Fig, a Moreton Bay: a gig, a fizzgig, an informer.

3. (Aus.) a busybody [= gig n.⁸ (3)].

1975		Bulletin (Sydney) 26 Apr. 46: If there were Mortons nearby (Morton Bay Figs: gigs, meaning busybodies) the knockaround would refer to whatever it was he didn’t want overheard as ‘gear.’.
1990		Tupper & Wortley Aus. Prison Sl. Gloss. 🌐 Moreton Bay fig. An intrusive person.