E. Cobham Brewer 1810–1897. Dictionary of Phrase and Fable. 1898.
Strap Oil.
A beating. A corruption of strap ’eil, i.e. German theil (a dole). The play is palpable. The “April fool” asks for a pennyworth of strap ’eil, that is dole of the strap, in French l’huile de cotret. (Latin, stroppus.)
