word processor vs word processing system

word processor and word processing system both are nouns.

Word	Noun	Adjective	Verb	Adverb
word processor	Yes	No	No	No
word processing system	Yes	No	No	No

As nouns, word processor and word processing system are synonyms defined as:

word processor and word processing system: an application that provides the user with tools needed to write and edit and format text and to send it to a printer

word processor (noun)	word processing system (noun)
an application that provides the user with tools needed to write and edit and format text and to send it to a printer	an application that provides the user with tools needed to write and edit and format text and to send it to a printer