Penetrant may refer to:
Penetrant (biochemical), a chemical that increases the ability of a poison to apply its toxic effect to a living organism Penetrant (mechanical, electrical, or structural), service of structural item penetrating a fire-resistance rated wall or floor assembly Penetrating oil, lubricant
See also Liquid penetrant, medium for Dye penetrant inspection Penetrance, in genetics, is the proportion of individuals carrying a particular variant of a gene