Prō

A Latin preposition signifying for, before, forth, being originally neuter dative for proi, Gr. πρὸ. In composition pro denotes fore, forth, forward.

Pro and con, for and against. — Pros and cons, things which may be said or urged for or against a thing; advantages or disadvantages. — Pro rata. [Lat. See Pro-RATA.] In proportion; proportion.