sanitize v.

1823, "pertaining to health or hygiene," from French sanitaire (1812), from Latin sanitas "health," from sanus "healthy; sane" (see sane). In reference to menstrual devices, by 1881 (in sanitary towel). In U.S. history the Sanitary Commission, created by the Secretary of War in 1861, provided relief to soldiers and oversaw military lodging and hospitals. Sanitarian is by 1859 as "promoter of, or one versed in, sanitary measures or reforms;" sanitarist in that sense also is by 1859.

word-forming element used to make verbs, Middle English -isen, from Old French -iser/-izer, from Late Latin -izare, from Greek -izein, a verb-forming element denoting the doing of the noun or adjective to which it is attached.

The variation of -ize and -ise began in Old French and Middle English, perhaps aided by a few words (such as surprise, see below) where the ending is French or Latin, not Greek. With the classical revival, English partially reverted to the correct Greek -z- spelling from late 16c. But the 1694 edition of the authoritative French Academy dictionary standardized the spellings as -s-, which influenced English.

In Britain, despite the opposition to it (at least formerly) of OED, Encyclopaedia Britannica, the Times of London, and Fowler, -ise remains dominant. Fowler thinks this is to avoid the difficulty of remembering the short list of common words not from Greek which must be spelled with an -s- (such as advertise, devise, surprise). American English has always favored -ize. The spelling variation involves about 200 English verbs.

"disinfectant, sanitizing agent," 1950, agent noun from sanitize.