(v) set (something or oneself) down with or as if with a noise, Syn. plunk, plonk, plop, flump, plunk down, plump down, plump, Example:He planked the money on the table; He planked himself into the sofa
v. i. [ Chiefly Colloq. ] 1. To make a quick, hollow, metallic, or harsh sound, as by pulling hard on a taut string and quickly releasing it; of a raven, to croak. [ Webster 1913 Suppl. ]
2. To drop or sink down suddenly or heavily; to plump. [ Webster 1913 Suppl. ]
3. To play truant, or “hooky”. [ Scot. ] [ Webster 1913 Suppl. ]