A person who grouses; a grumbler / (nautical) A temporary pile driven into the bottom of a river to hold a boat in position; a spud

By means of introns

(military, US) Initialism of reporting unit code.

A small red worm or larva, used as bait for fish. / A young salmon or parr, in the stage in which it has transverse black bands, as if burned by a gridiron.