fathom vs linear unit

fathom and linear unit both are nouns.

Word	Noun	Adjective	Verb	Adverb
fathom	Yes	No	Yes	No
linear unit	Yes	No	No	No

As nouns, linear unit is a hypernym of fathom; that is, linear unit is a word with a broader meaning than fathom:

Other hypernyms of fathom include linear measure.

fathom (noun)	linear unit (noun)
a linear unit of measurement (equal to 6 feet) for water depth	a unit of measurement of length
(mining) a unit of volume (equal to 6 cubic feet) used in measuring bodies of ore

fathom (verb)	linear unit (verb)
measure the depth of (a body of water) with a sounding line
come to understand