Green’s Dictionary of Slang

(orig. US) working, operating or open at night, e.g. owl shift, the night shift, owl car, a late-night streetcar.

1856		N.Y. Herald 8 Jan. 1/2: The ‘Owl Train,’ due at Jersey City at five o’clock yesterday morning, did not arrive until afternoon [DA].
1866		Congressional Globe 26 Mar. 1641/2: He is expected to take the owl-line, the midnight line, as it passes his house .
1889		Farmer Americanisms 405/2: Owl-car, a tram-car plying late into the night [DA].
1896		Salt Lake Herald (UT) 10 May 8/2: Sergeant Eslinger [...] had charge of the ‘owl shift’.
1896		F. Hutcheson Barkeep Stories 8: The occasional rattle of the State street owl cars.
1901		Bulletin (Sydney) 2 Nov. 13/2: Sydney tram authorities charge double fares on the ‘owl cars’ (Brisbane name, borrowed from Yankeeland, for all-night trams).
1916		J. Lait ‘Taxi, Mister!’ in Beef, Iron and Wine (1917) 137: When a keen newspaper reporter wants to find out anything of what is going on in his town he sees the police, buzzes the night clerk in the owl drug-store.
1916		Day Book (Chicago) 19 June 9/2: Wanted to Rent [...] three connecting rooms [...] near an owl car line; man works at night.
1923		M. Watts Luther Nichols 218: Them old owl-cars don’t run but once an hour [DA].
1932		W.R. Burnett Giant Swing 56: An owl-car was standing at the end of the Avenue A line.
1947		F. Brown Fabulous Clipjoint (1949) 123: I walked down to Grand, and was lucky enough to see an owl car coming.