To sit in on a conversation, meeting, card-game or online chat and offer unsolicited, informal comments. The original meaning from Yiddish (kibitzen, derived from German kiebitzen - to be an onlooker or spectator) had a negative connotation of being a busybody or giving intrusive, meddlesome, unwanted advice. However, in contemporary US usage, it has become friendlier.
She's meeting with some suits this afternoon, do you want to come kibitz and liven things up?

I'm not here as a formal participant, I'm just kibitzing.

Quit kibitzing! I know how to play Texas hold 'em.
by LiamK2 January 17, 2011
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Kibitz: to sit out of a game and just watch.

Derivatives include kibitzing and kibitzed.
"Do you want to play poker?"
"No thanks, I'll play kibitz."
by Potatoes March 4, 2006
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to give unwanted or intrusive advice to someone in a game or performance while watching(from German Via Yiddish)
Stop Kibitzing and watch the show. (example of kibitz)
by The Return of Light Joker August 22, 2009
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someone being a spectator of some play (ex. card game or chess game) who expresses his support to his beloved players by commenting it or giving some advice (often unwanted, idle, unsolicited). His action is that he "kibitzes" (it could mean also 2) that he converse idly and giving unwanted advice).

The synonym is kibbitzer.

The word comes from Yiddish, and there are two possible etymologies:
1) from German word "Kiebitz" meaning "lapwing" (or "kibitz" as well, maybe secondary Yiddish influence) or cognate to it "kiebitzen" ("to look on / to kibitz"); Why lapwing? Because in early usage of the word, the kibic was just standing, staring and hearing - what that birds are seeming to do.
2) from Hebrew root "" represented ex. by the word "leqabetz" meaning "to collect, to assemble" - probably because in XIX century Hasidim (Hasidic Jews) were enthusiastically assembling (ex. in Polish lands) around their Tzadik (Rebbe) to look on him and hear his spiritual message; the cognate of this word is kibbutz - a collective community in Israel that was traditionally based on agriculture;
3) from Hebrew word "qobesh" - "to conquere" (this suggestion I found in German Wikipedia, but it wasn't more precisely explained).

The Yiddish word is also a source for Polish word kibic (pronounces in this same way), which denotes (mostly football) sports fan committed to the chosen team. What he's doing is "kibicować" (to look on and cheer sb on esp. in a football play).
Yosef Tunkel, a Yiddish writer from Belarus, came to the U.S. and published a humorous journal called Der kibitser in 1909 and 1910. And 1910 is also the earliest I've found for the use of the word in English:
"At a beer saloon on the East Side, which has a clubroom annex, where skat and pinochle are the chief attractions, but where visitors who are not satisfied with playing the silent part of "kibitz" discuss intricate problems in science, religion, politics and statecraft, a placard was posted yesterday showing a rampant ram and this legend in German: "Theodore Roosevelt is on time for everything. He will reach Germany in the bock beer season and will drink bruderschaft with the Kaiser in ---- beer. Prosit!" —New York Tribune, May 13, 1910

From German Kiebitz, an annoying onlooker at a card game (actually a certain bird that typically takes over the nests of other kinds of birds). The Yiddish meaning apparently comes from the fact that onlookers at a game often amuse themselves at the players' expense.
by UrbanD. KIBIC April 25, 2020
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A top secret organization that is devoted to stealing people's passwords and talking about music.
by Reynard March 1, 2004
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To meddle and give unwanted advice. kuh-Ib-itz
by The Man December 1, 2004
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1.) Yiddish word for a spectator, especially in chess.

2.) Someone who gives unwanted advice, which was never asked for or is irrelevant.

3.) Someone who gives advice to people!
1.) Moshe down the street was the kibitzer for our chess match!


3.) He's such a good kibitzer, ever since he's told me to kill my family with NapTime, the house has been 100% quiet!
by crazykibitzer June 3, 2022
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