prŏtăsis, is, f., = πρότασις.
I An assertion , proposition (pure Lat. effatum), Ap. Dogm. Plat. p. 29.—
II The beginning or first part of a play , Don. Ter. And. praef.
·noun A proposition; a maxim. II. Protasis ·noun The first part of a drama, of a poem, or the like;...
Webster's Dictionary of the English Language