Green’s Dictionary of Slang

1. a clergyman.

1829

Vidocq Memoirs (trans. W. McGinn) I 218: All that is very fine, if one’s scrag was not in danger [...] but with Jack Ketch on one side, and the black sheep (clergyman) on the other, and the traps (gendarmes) behind, it is not quite so pleasant to be turned into food for flies.

2. a strike-breaker.

1832		Times 10 Dec. 4/2: Some, however, who were not members of the Trades’ Union, remained in his employ [...] by which they became, in the slang of the Union, black sheep.
1858		Oxford U. Herald 9 Oct. 5/2: In connection with the strike at oaks Colliery [...] several men have been sentenced to imprisonment for [...] attacks upon the ‘black sheep’.
1878		Sheffield Dly. Teleg. 18 Apr. 3/4: The dispute at the Colliery is as far as ever from being settled and a fresh batch of new hands [...] arrived [...] and were billeted at what is now termed ‘Black Sheep Hall’.
1887		Dly Eve. Bulletin (Maysville, KY) 25 Jan. 1/2: Longshoremen’s Strike [...] A boarding house has been fitted up at the mill to accomodate the ‘black sheep’.
1889		Derby Dly Teleg. 16 Sept. 3/1: At the Royal Albert Docks the strike men [...] found the so-called black sheep at work. They declared they would not work with non-union men.
1891		Pittsburgh Dispatch (PA) 28 Apr. 5/2: It is also reported that there was a strike among the black sheep [...] on account of a reduction in their wages to pay the deputies.
1901		Bourbon News (KY) 2 Aug. 1/3: The kids is called ‘lambs’ — ‘black lambs’ — when their father goes to be a black sheep and I’ll never be a lamb, I’m fur the strikers.

3. attrib. use of sense 1.

1902

Bulletin (Sydney) 13 Sept. 36/1: There’d be intellectual conversation for the benefit of black-sheep new-chums.