Green’s Dictionary of Slang

1. a Quaker.

1664		R. Howard The Committee IV i: Who wou’d have believ’d that we Shou’d have liv’d to have seen Obadiah overcome with the Creature?
1761		Memoirs of [...] Jane D****s 116: Obediah Broad-brim, who tho’ he was full of the spirit had not entirely subdued the lusts of the flesh.
1825		Pierce Egan’s Life in London 9 Oct. 301/3: [H]e found Obadiah locked up in a room.
1838		‘Uncle Sam’s Peculiarities’ Bentley’s Misc. IV 48: Philadelphia had attracted none but the real Simon Pures, Obadiah Broadbrims, and Grey Susannahs.
1855		Broadway Belle (NY) 1 Oct. n.p.: Quaker Courtship. [...] Hum, truly Obadiah, thou has wisely said.
1869		Western Gaz. 5 Mar. 5/1: ‘Obadiah’ [...] our unfortunate neighbour is monomaniac.
1877		Pall Mall Gaz. 22 May 10/1: The Young Obadiah and the old Obadiah. Mr [John] Bright is his younger days was often violent and unreasonable.

2. (Aus.) any variety of repressive puritan.

1904

Sydney Sportsman (Surry Hills, NSW) 2 Nov. 1/1: Australians [...] will bet on a horse race, or any thing else, and the sooner Obadiah and Emanuel and Zeikiel and Jacob recognize this fact and moderate their extreme views the better will it be.