nux, n.² — Green’s Dictionary of Slang

nux n.²

[abbr. medical Lat. nux vomica, the fruit from which strychnine is produced]

(US prison) prison-cooked tea.

1918		H. Simon ‘Prison Dict.’ in AS VIII:3 (1933) 30/1: NUX. Tea.
1949		Monteleone Criminal Sl. (rev. edn).
1950		Goldin et al. DAUL 1471/2: Nux. (Leavenworth Federal Prison) The tea served in the prison mess-hall.