What is "per-"

Per- \Per-\ [See Per.]

1. A prefix used to signify through, throughout, by, for, or as an intensive as perhaps, by hap or chance; perennial, that lasts throughout the year; perforce, through or by force; perfoliate, perforate; perspicuous, evident throughout or very evident; perplex, literally, to entangle very much.

2. (Chem.) Originally, denoting that the element to the name of which it is prefixed in the respective compounds exercised its highest valence; now, only that the element has a higher valence than in other similar compounds; thus, barium peroxide is the highest oxide of barium; while nitrogen and manganese peroxides, so-called, are not the highest oxides of those elements.

word-forming element meaning "through, throughout; thoroughly; entirely, utterly," from Latin preposition per (see per (prep.)).

Etymology 1 pre. 1 (context non-productive English) In verbs: denoting the sense "through", as in '''perforate'''. 2 (context non-productive English) In verbs: denoting the sense "thoroughly", as in '''perfect'''. 3 (context non-productive English) In verbs: denoting the sense "to destruction", as in '''pervert'''. 4 (context non-productive English) In adjectives and adverbs: denoting the sense "extremely", as in '''perfervid'''. 5 (context chemistry English) Forming nouns and adjectives denoting the maximum proportion of one element in a compound, as in '''peroxide'''. 6 (context chemistry English) Added to the name of an element in a polyatomic ion denote the number of that element (usually four). Etymology 2

pre. (context non-productive English) Denoting the sense "by" or "per", as in '''perchance''' or '''perhaps'''.