threshold vs limen

threshold and limen both are nouns.

Word	Noun	Adjective	Verb	Adverb
threshold	Yes	No	No	No
limen	Yes	No	No	No

As nouns, threshold and limen are synonyms defined as:

threshold (noun)	limen (noun)
the sill of a door; a horizontal piece of wood or stone that forms the bottom of a doorway and offers support when passing through a doorway	the smallest detectable sensation
the entrance (the space in a wall) through which you enter or leave a room or building; the space that a door can close
the smallest detectable sensation
a region marking a boundary
the starting point for a new state or experience