Green’s Dictionary of Slang

1. the chin.

1935		A.J. Pollock Und. Speaks.
1949		Monteleone Criminal Sl. (rev. edn).
1953		Berrey & Van den Bark Amer. Thes. Sl. (2nd edn).
1963		L.F. Freed Crime in S. Afr. 106: His ‘thick and thin’ [is] his chin.
2002		B. Kirkpatrick Wicked Cockney Rhy. Sl.

2. gin.

1928		M.C. Sharpe Chicago May: Her Story in Hamilton (1952) 132: Thick and thin – gin.
1952		Argus (Melbourne) 13 June 4s/2: If, however, he consumes too much ‘pig’s ear ’ or ‘thick and thin’, he may finish up mollies [...] contracted from ‘mollie the monk’.
1967		‘Whisper All Aussie Dict.’ in Kings Cross Whisper (Sydney) xli 4/3: thick and thin: [...] gin.
2002		B. Kirkpatrick Wicked Cockney Rhy. Sl.

3. (Aus.) the skin.

2002

Pete’s Aussie Sl. Home Page 🌐 thick and thin: the skin.