|a printed punctuation mark (‽), available only in some typefaces, designed to combine the question mark (?) and the exclamation point (!), indicating a mixture of query and interjection, as after a rhetorical question.|
|an extraordinary or unusual thing, person, or event; an exceptional example or instance.|
|Professional Employment Register|
|3.||away, beyond: perfidy|
|4.||completely, throughly: perplex|
|6.||indicating that a chemical compound contains a high proportion of a specified element: peroxide; perchloride|
|7.||indicating that a chemical element is in a higher than usual state of oxidation: permanganate; perchlorate|
|8.||(not in technical usage) a variant of peroxy- : persulphuric acid|
|[from Latin per through]|
Thoroughly; completely; intensely: perfuse.
Containing an element in its highest oxidation state: perchloric acid.
Containing a large or the largest possible proportion of an element: peroxide.
Containing the peroxy group: peracid.