as in fool
a silly flighty person
in a medical situation of this seriousness we don't need some rattlebrain running around in a panic
Synonyms & Similar Words
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Example Sentences
Recent Examples of Synonyms for rattlebrain
Noun
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Here are three fool-proof tips to stay ahead of the curve during the volatility to come.—
Solo Ceesay,
Rolling Stone,
7 May 2026 -
The Quince Revive Nylon Crescent Shoulder Bag is just $32, but don’t let its affordable price fool you.—
Destinee Scott,
Travel + Leisure,
7 May 2026
Noun
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But no, sillies: Bradley is white, famous and pretty — no jail time for her!—
Kimberly Roots,
TVLine,
17 Sep. 2025
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It was shot in portrait because it was shot in Instagram by and for a woman who was losing her mind in quarantine and had fully let the sillies take the wheel.—
Ego Nwodim,
TIME,
12 Feb. 2025
Noun
-
Atvara, who spent years working in teaching, journalism, and marketing before returning to her first love, puts her classical training to good use, particularly during a goose-bump-inducing climax in which her voice swoops and soars like a haunted songbird.—
Jon O'Brien,
Vulture,
11 May 2026
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Their first album in four years, Dancing on the Wall, reflects a group that's been famous long enough to know what a golden goose’s underbelly looks like.—
Nina Corcoran,
Pitchfork,
8 May 2026
Noun
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One page has handbag ideas, and, true to form, there is a cuckoo-clock purse, a pyramid purse, a purse shaped as a well.—
Adam Moss,
Vulture,
17 Apr. 2026
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The Thunder’s main stopper is cuckoo for closeouts.—
Fred Katz,
New York Times,
2 Apr. 2026
Noun
-
Winnie, on the other hand, is a flibbertigibbet of stream-of-consciousness.—
Han Ong,
New Yorker,
22 June 2025
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Duvall is a big reason why: All the film’s insights into the slipperiness of identity are there in her casually virtuosic, veritable dual performance, in which a funny flibbertigibbet loses hold of herself as the world around seems to splinter into something frighteningly new.—
A.A. Dowd,
Vulture,
19 July 2024
Noun
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There’s a tramp, a ditz, a bad boss, a hippie, a by-the-book good girl.—
Emily Nussbaum,
New Yorker,
2 Apr. 2026
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Rather than stay pigeonholed as a ditz, Simpson (who just released new music for the first time in 15 years) went on to launch her own fashion brand, which hit $1 billion in sales in 2015 and is still going strong today.—
EW Staff,
EW.com,
20 Mar. 2025
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Cite this Entry
“Rattlebrain.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/rattlebrain. Accessed 18 May. 2026.
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