A popular term often used on social media in response to a sentimental, sappy, or emotionally-charged video or meme that makes you "tear-up". It's a metaphor referring to how your eyes water when you're cutting onions. The phrase is used by the poster as a means of deflecting or "saving face" from admitting they were emotionally affected to the point of tears welling in their eyes from what they just saw or read.
VIDEO POSTED ON FACEBOOK: (Something with a kitten getting rescued from a house fire by a firefighter that gives it oxygen and revives it. Then, the firefighter unites it with the ecstatic little girl it belongs to.)

SOMEONE AFTER VIEWING THE VIDEO: Just watched this video and my eyes started tearing up from those damn onions again!
by Hextraordinary13 February 6, 2017
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When Woods tells Mason that he is "a god damn onion"
Mason: "Yeah, you're the master of quiet."
Woods: "I'm a god damn onion Mason!"
by Maxipedia May 29, 2023
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