Main Entry: hy·dron·ic

Pronunciation: \hī-ˈdrä-nik\

Function: adjective

Etymology: hydr- + -onic (as in electronic)

Date: 1946

: of, relating to, or being a system of heating or cooling that involves transfer of heat by a circulating fluid (as water or vapor) in a closed system of pipes

— hy·dron·i·cal·ly \-ni-k(ə-)lē\ adverb