fogey, n. — Green’s Dictionary of Slang

fogey n.

[Fr. fourgeaux, fierce, fiery or Scot. dial. foggy, fat, bloated. Note SE fogram/fogrum, an old-fashioned, out-of-date person]

1. (also foggy) an invalid soldier [thence the SE use, usu. with pfx old].

1785, 1788, 1796		Grose Classical Dict. of the Vulgar Tongue.
1811		Lex. Balatronicum.
1812		letter cited in N&Q Ser. 6 IX 10: My company is now forming into an invalid company. Tell your grandmother we will be like the Castle foggies [F&H].
1823		Egan Grose’s Classical Dict. of the Vulgar Tongue.

2. an old maid.

1848

G.W.M. Reynolds Mysteries of London II (2nd series) 159: Them ould fogeys down stairs in the yard.