Is it ensure, insure, or assure?
also mould, "hollow shape," c.1200, originally "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" (see mode (1)). From c.1300 as "pattern or model by which something is shaped or made." To break the mold "render impossible the creation of another" is from 1560s.
also mould, "furry fungus," early 15c., 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, "loose earth," Old English molde "earth, sand, dust, soil; land, country, world," from Proto-Germanic *mulda (cf. 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 rub, grind" (see meal (n.2)). Specifically, since late (Christian) Old English, "the earth of the grave."
also mould, mid-14c., "to mix, blend;" late 14c. "to knead, shape," from mold (n.1). Figurative sense (of character, etc.) is from c.1600. Related: Molded; molding.
mold 1 (mōld)
A shaped receptacle into which material is pressed or poured in making a cast.
A frame around which something is formed or shaped.
The shape of an artificial tooth or teeth.
To shape a mass of plastic material in or on a mold.
To change in shape. Used especially of the adaptation of the fetal head to the pelvic canal.
Any of various filamentous fungi, generally a circular colony having a woolly or furry appearance, that grow on the surface of organic matter and contribute to its disintegration.
Any of various fungi that often form a fuzzy growth (called a mycelium) on the surface of organic matter. Some molds cause food to spoil, but others are beneficial, such as those used to make certain cheeses and those from which antibiotics like penicillin are developed. The molds do not form a distinct phylogenetic grouping but belong to various phyla including the ascomycetes and the zygomycetes. See also slime mold.