Green’s Dictionary of Slang

(UK Und.) an idler, a casual labourerer.

1861

(con. 1840s–50s) H. Mayhew London Labour and London Poor III 300/1: On the platform surrounding the Commercial Dock basins are a number whom I have heard described as ‘idlers,’ ‘pokers,’ and ‘casual labourers.’ These men are waiting in hopes of a job, which they rarely obtain until all the known hands have been set to work.