How is “not for nothing” used?

In Mighty Aphrodite (1995), one line is: “Well, I used to date a pinball champ, not for nothing.”

Which movie is “not for nothing” from?

The clip at the top of this page is from Mighty Aphrodite (1995).

Well, I used to date a pinball champ, not for nothing.

8 作品で登場 · 1 本目

for a very good reason; A spoken lead-in before a blunt, critical, or nosy remark, signaling the speaker is about to say it anyway.

10 本の映画に登場

オックスフォード映画の 60%
for a very good reason
Well, I used to date a pinball champ, not for nothing.
I will not say you shall see a masque, but if you do, it was not for nothing that my nose fell a-bleeding on Black Monday last at six o'clock in the morning.
編集映画の 40%
A spoken lead-in before a blunt, critical, or nosy remark, signaling the speaker is about to say it anyway.
You know, Mookie, not for nothing,
Hey, not for nothing, dude, but this kid really hates his mother.

定義：Oxford Advanced Learner's Dictionary 第 9 版