capillary fracture vs hairline fracture

capillary fracture and hairline fracture both are nouns.

Word	Noun	Adjective	Verb	Adverb
capillary fracture	Yes	No	No	No
hairline fracture	Yes	No	No	No

As nouns, capillary fracture and hairline fracture are synonyms defined as:

capillary fracture and hairline fracture: a fracture without separation of the fragments and the line of the break being very thin

capillary fracture (noun)	hairline fracture (noun)
a fracture without separation of the fragments and the line of the break being very thin	a fracture without separation of the fragments and the line of the break being very thin