mandril vs mandrel

mandril and mandrel both are nouns.

Word	Noun	Adjective	Verb	Adverb
mandril	Yes	No	No	No
mandrel	Yes	No	No	No

As nouns, mandril and mandrel are synonyms defined as:

mandril and mandrel: any of various rotating shafts that serve as axes for larger rotating parts

Other synonyms of mandril include arbor, spindle.

mandril (noun)	mandrel (noun)
any of various rotating shafts that serve as axes for larger rotating parts	any of various rotating shafts that serve as axes for larger rotating parts