Any plant of the genus Rheum, especially Rheum rhabarbarum, having large leaves and long green or reddish acidic leafstalks that are edible, in particular when cooked (although the leaves are mildly poisonous).

Of the colour of rhubarb: either brownish-yellow (the colour of rhubarb rhizomes and roots used for medicinal purposes), or pale red (often the colour of the leafstalks of common rhubarb).

(Britain, military, aviation) Of fighter aircraft: to fire at a target opportunistically.

(originally theater, uncountable) General background noise caused by several simultaneous indecipherable conversations, which is created in films, stage plays, etc., by actors repeating the word rhubarb; hence, such noise in other settings.

(intransitive, originally theater) Of an actor in a film, stage play, etc.: to repeat the word rhubarb to create the sound of indistinct conversation; hence, to converse indistinctly, to mumble.

Alternative form of rhubarb rhubarb

(film) Background noise of simultaneous conversations, none of which is decipherable since the actors are repeating the word rhubarb or other words with similar attributes.

plural of rhubarb.

Third-person singular simple present indicative form of rhubarb

simple past tense and past participle of rhubarb.