full of prunes

full of prunes

Nonsensical. From the idea that prunes cause gas (and being "full of hot air" is synonymous with "nonsensical"). His explanation is totally full of prunes and doesn't answer the question at all.
See also: full, of, prune
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.

full of prunes

mod. full of nonsense. (see also full of beans. Prunes can cause gas = hot air = nonsense.) You’re just silly. Completely full of prunes.
See also: full, of, prune
McGraw-Hill's Dictionary of American Slang and Colloquial Expressions Copyright © 2006 by The McGraw-Hill Companies, Inc. All rights reserved.
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References in periodicals archive ?
There is an old saying, 'full of prunes,' meaning to talk nonsense.