just because adverb3 •Used to show that the truth or existence of one thing does not logically justify the truth or existence of another thing.Just because he didn't accept your friend request (it) doesn't mean he has forgotten you nor does it imply that he no longer wants to be friends with you. •For no particular reason.When they asked him why it had to be that way, "Well," he answered, "just because." — 1975 •Used to say that something has insufficient grounds for being done.[My banishment was p]etty spite on the part of the Lord President, just because they [my lab mice] et his cat. — 1985