LER

Set to 5 different clues across 12 published puzzles, most often “Celtic Neptune” — The New York Times, Sunday, 30 January 2005.

3 letters

Every clue on record, most used first

Celtic Neptune5 times
The New York Times — Sunday, 30 January 2005
Celtic sea god4 times
The New York Times — Wednesday, 1 December 2010
Personification of the sea, in mythonce
The New York Times — Sunday, 8 August 1999
Celtic Poseidononce
The New York Times — Sunday, 29 December 1996
Manannan's father, in mythonce
The New York Times — Saturday, 29 October 1994