Green’s Dictionary of Slang

hole in the wall n.

[either f. the holes in the walls of English debtor’s prisons, through which the inmates could obtain supplies and money to alleviate their situation, or f. the small shops and similar establishments found in the broad stone walls of fortified medieval cities. Hole in the wall became a generic term, although the US West had its Hole in the Wall, an outlaw hideaway in the gorges and cliffs that straddle the Wyoming, Colorado and Utah state lines (a sometime refuge for Butch Cassidy and the Sundance Kid and the real-life Wild Bunch), while 1860s New York City boasted the Hole in the Wall on Water Street, where its proprietor, Gallus Meg (a monstrous Englishwoman), bit the ears off ill-behaved customers and preserved her trophies in a pickle jar displayed behind the bar]

1. [mid-17C] a brothel.

2. [mid-19C–1930s] (US) an illicit liquor store or bar; see also sense 6.

3. [mid-19C–1950s] a small shop.

4. [mid-19C+] (US, also hole in the road) a small, insignificant, remote place.

5. [late 19C+] a tiny, cramped apartment.

6. [1910s+] (US) a bar; see also sense 2.

7. [1920s–40s] a restaurant.

8. [1980s+] an automatic teller machine (ATM), installed in the external wall of a bank or building society branch.