Green’s Dictionary of Slang

a silent breaking of wind, ‘more obvious to the nose than to the ears; frequently by old ladies charged on their lapdogs’ (Grose, 1796).

1680		M. Stevenson Wits Paraphras’d 114: But a Fice smother’d in the skin, / When it’s not out, stinks worse within.
c.1786		Grose Classical Dict. of the Vulgar Tongue ms. additions n.p.: Fice or Foyse, a Small Windy Escape Backwards.
1788, 1796		Grose Classical Dict. of the Vulgar Tongue (2nd, 3rd edn) n.p.: Fice, or Foyse. A small windy escape backwards, more obvious to the nose than ears; frequently by old ladies charged on their lap-dogs.
1811		Lex. Balatronicum.
1823		Egan Grose’s Classical Dict. of the Vulgar Tongue.