chiefly British English spelling of mold (q.v.) in various senses. Related: Moulded; moulding.

antibiotic agent active against bacteria but harmless to most persons, 1929, coined in English by Alexander Fleming (1881-1955), who first recognized its antibiotic properties, from Modern Latin Penicillium notatum (1867), the name of the mould from which it was first obtained, from Latin penicillus "paintbrush" (see pencil (n.)), in reference to the shape of the mould cells.

also mould, mid-14c., "to mix, blend (something) by kneading;" late 14c. "to knead (bread), form into a particular shape," from mold (n.1). Figurative sense (of character, etc.) is from c. 1600. Related: Molded; molding.

also mould, "minute, furry fungus," especially the types growing on neglected food and decaying organic matter, c. 1400, molde, probably from moulde, past participle of moulen "to grow moldy" (early 13c.), related to Old Norse mygla "grow moldy," possibly from Proto-Germanic *(s)muk- indicating "wetness, slipperiness," from PIE *meug- (see mucus). Or it might have evolved from (or been influenced by) Old English molde "loose earth" (see mold (n.3)).

also mould, "hollow pattern of a particular form by which something is shaped or made," c. 1200, originally in a figurative sense, "fashion, form; nature, native constitution, character," metathesized from Old French modle "model, plan, copy; way, manner" (12c., Modern French moule), from Latin modulum (nominative modulus) "measure, model," diminutive of modus "manner" (from PIE root *med- "take appropriate measures").

By c. 1300 as "form into which molten metal, etc., is run to obtain a cast." By 1570s as "a form of metal or earthenware (later plastic) to give shape to jellies or other food. Figurative use of break the mold "render impossible the creation of another" is from 1560s.

"fine, soft, loose earth," Old English molde "earth, sand, dust, soil; land, country, world," from Proto-Germanic *mulda (source also of Old Frisian molde "earth, soil," Old Norse mold "earth," Middle Dutch moude, Dutch moude, Old High German molta "dust, earth," Gothic mulda "dust"), from PIE root *mele- "to crush, grind." Specifically, since late (Christian) Old English, "the earth of the grave." Also, from c. 1300 as "earth as the substance out of which God made man; the 'dust' to which human flesh returns."

The proper spelling is mold, like gold (which is exactly parallel phonetically); but mould has long been in use, and is still commonly preferred in Great Britain. [Century Dictionary, 1897]

late 14c., matris, matrice, "uterus, womb," from Old French matrice "womb, uterus" and directly from Latin mātrix (genitive mātricis) "pregnant animal," in Late Latin "womb," also "source, origin," from māter (genitive mātris) "mother" (see mother (n.1)).

The many figurative and technical senses are from the notion of "that which encloses or gives origin to" something. The general sense of "place or medium where something is developed" is recorded by 1550s; meaning "mould in which something is cast or shaped" is by 1620s; sense of "embedding or enclosing mass" is by 1640s.

The mathematical sense of "a rectangular array of quantities (usually square)" is because it is considered as a set of components into which quantities can be set. The logical sense of "array of possible combinations of truth-values" is attested by 1914. As a verb, in television broadcasting, from 1951.