user vs tweep

user and tweep both are nouns.

Word	Noun	Adjective	Verb	Adverb
user	Yes	No	No	No
tweep	Yes	No	No	No

As nouns, tweep is a hyponym of user; that is, tweep is a word with a more specific, narrower meaning than user:

user: a person who makes use of a thing; someone who uses or employs something
tweep: A person using Twitter

Other hyponyms of user include consumer, end user, usufructuary, utiliser, utilizer, wearer.

user (noun)	tweep (noun)
a person who makes use of a thing; someone who uses or employs something	A person using Twitter
a person who uses something or someone selfishly or unethically
a person who takes drugs