"a blower," also "an apparatus for forcing air or carbon dioxide into water or other liquids," 1861, agent noun from aerate (v.).
Entries linking to aerator
aerate v.
"cause to mix with carbonic acid or other gas," 1794 (implied in aerated), from aer/aër (used in old science for specific kinds of air, a sense later given to gas (n.1)), from Latin aer (see air (n.1)) + verbal suffix -ate (2). The meaning "expose to air" is from 1799, probably a back-formation from aeration. Related: Aerating.