The name is either an elaborate feminine form of Henry (Estonian male names Ent, Endo), or it is most likely taken from the name of a place in Estonia. It is both the name of a lake and nature preserve. Lake Endla is quite often referenced in Estonian folk poetry.
The masculine version is Endel.
Other feminine forms include: Enda, Enna and Enn.
The designated name-day is June 8.