humectant

English Thesaurus

1. any substance that is added to another substance to keep it moist (noun.substance)

hypernym	:	substance,
definition	:	a particular kind or species of matter with uniform properties (noun.tops)

hyponym	:	propanediol, propylene glycol,
definition	:	a sweet colorless, viscous, hygroscopic liquid used as an antifreeze and in brake fluid and also as a humectant in cosmetics and personal care items although it can be absorbed through the skin with harmful effects (noun.substance)