Per

1. Common first name in Scandinavia. A form of Peter which means "rock" or "cliff" in Latin.

1. Per (?), prep. [L. Cf. Far, For-, Pardon, and cf. Par, prep.]

Through; by means of; through the agency of; by; for; for each; as, per annum; per capita, by heads, or according to individuals; per curiam, by the court; per se, by itself, of itself. Per is also sometimes used with English words.

Per annum, by the year; in each successive year; annually. — Per cent, Per centum, by the hundred; in the hundred; — used esp. of proportions of ingredients, rate or amount of interest, and the like; commonly used in the shortened form per cent. — Per diem, by the day. [For other phrases from the Latin, see Quotations, Phrases, etc., from Foreign Languages, in the Supplement.]

PER can also mean PE ratio (price-to-earnings ratio, used in finance).