hobber vs hobbing machine

hobber and hobbing machine both are nouns.

Word	Noun	Adjective	Verb	Adverb
hobber	Yes	No	No	No
hobbing machine	Yes	No	No	No

As nouns, hobber and hobbing machine are synonyms defined as:

hobber and hobbing machine: a special type of milling machine used for gear cutting, cutting splines, and cutting sprockets.

hobber (noun)	hobbing machine (noun)
a special type of milling machine used for gear cutting, cutting splines, and cutting sprockets.	a special type of milling machine used for gear cutting, cutting splines, and cutting sprockets.