The Collaborative International Dictionary of English v.0.48:
Tablespoonful \Ta"ble*spoon`ful\, n.; pl. Tablespoonfuls. As much as a tablespoon will hold; enough to fill a tablespoon. It is usually reckoned as one half of a fluid ounce, or four fluid drams. [1913 Webster]WordNet (r) 3.0 (2006):
tablespoonful n 1: as much as a tablespoon will hold [syn: tablespoon, tablespoonful]