adj. Largest, greatest (in magnitude), highest, most.n. The element of a set with the greatest magnitude.n. Said of an ideal of a ring or a filter of a lattice: that it is as large as it can be without being trivial (improper).n. Said of a set of well-formed formulas: that it is as large as it can be without being inconsistent; i.e., that for any wff φ, the set contains either φ or ~φ.