Green’s Dictionary of Slang

1. (US campus, also squash-head, squashie, squashy) a fool; thus squash-headed adj., foolish.

1855		Democrat & Sentinel (Ebensburg, PA) 4 Jan. 1/4: The notorious Washer or Squash-head, told Governor Young ‘that he had been mad, and had acted foolishly’.
1866		H.L. Williams N.-Y. After Dark 37: Look here, girl, don’t you get up your back against me – I ain’t a country squash to stand any of your slack!
1889		Burnley Exp. 12 Jan. 2/6: ‘Country boys aren’t such squash-heads as they sometimes look’.
1896		W.C. Gore Student Sl. in Cohen (1997) 12: squash n. A foolish, ‘soft’ fellow.
1915		M.G. Hayden ‘Terms Of Disparagement’ in DN IV:iii 201: squash, a vacillating person. ‘I say you are a squash, but I hardly think you have that much backbone.’.
1922		Salt Lake Telegram (Salt Lake City, UT) 28 Oct. 5/6: [advert] Laugh at Toby as ‘The Squash Head’ Hippodrome Theatre.
1947		Camden News (AR) 4 Dec. 1/4: ‘Stamps-Baxter Melody Boys’ featuring ‘Joe Squash-Head’ the South’s Most Popular Comedian.
1962		A. La Guma Walk in the Night (1968) 52: He reached for his bottle of cheap wine. [...] ‘You better go slow on that,’ the girl, Nancy, said. ‘I can take it,’ Willieboy said thickly. ‘What do you think I am? A squashie?’ [Ibid.] 75: Blerry young squashy, Michael Adonis thought [...] For what’s he got to act like a blerry godfather?
1963		C. Cooper Jr ‘Yet Princes Follow’ in Black! (1996) 255: What squash-head took a fifty-dollar play on one-a slip! What-a squash-head!
1966		‘Tom Pendleton’ Iron Orchard (1967) 14: Big squash-headed sonofabitch thinks he owns the place.
1995		Tampa Trib. (FL) 4 Sept. 9/1: The students had signed a greeting card referriung to Rep. Wallace as a ‘squish head,’ ‘squash head’ and a butthead.

2. (US) the head, face.

1938		J. Weidman I Can Get It For You Wholesale 59: All you had to do was take one look at his squash to see that he believed it.
1950		Goldin et al. DAUL 206/1: Squash. (New England) The face; the head.
1972		B. Rodgers Queens’ Vernacular 144: out of one’s squash very drunk, high or mad. [Ibid.] 188: squash (fr black sl) head, by extension brains.
1987		T. Wolfe Bonfire of the Vanities 290: Guy’s so hung over, he’s bleeding into his squash.