plank1exclamationa warning call to make someone hide:Plank! Hornies binging! [Hide! Watch out! police coming!]20-. etymology: probably a development from Scots plank, verb ‘to hide’; Grose and Egan (1823) attested ‘plank ‘to hide’ as Scotch Cant’; also attested in Shelta and by BW
plank2verbput in a secret place, hide, stow away for later use:plank the bairns’ praisents. [hide the childrens’ presents]19-. etymology: Scots but origin obscure; attested by Grose and Egan (1823) as ‘Scotch Cant’; attested by JS