lactone noun. ['laktǝʊn] M19.
[from LACTO- + -ONE.]
Chemistry.
1. A volatile liquid obtained on heating lactic acid. Only in M19.

2. Any of the class of cyclic esters formed (as) by the elimination of a molecule of water from a carboxylic acid, and characterized by the group OCO as part of a ring. L19.

[TahlilGaran] English Dictionary ▲