rattlebrain

noun

ˈra-tᵊl-ˌbrān How to pronounce rattlebrain (audio)
Definition of rattlebrainnext
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
  1. fool
  2. silly
  3. goose
  4. cuckoo
  5. flibbertigibbet
  6. ditz
Noun
  • Don’t let the thin sole fool you though, the structure is still quite supportive and keeps your feet cushioned.
    — Rylee Johnston, PEOPLE, 11 July 2026
  • Being a gent or a supplicant wasn’t the same as being a fool, though.
    — Nicholas Quah, Vulture, 29 June 2026
Definition of fool
Noun
  • But no, sillies: Bradley is white, famous and pretty — no jail time for her!
    — Kimberly Roots, TVLine, 17 Sep. 2025
  • 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
Definition of silly
Noun
  • Unlike caviar, though, Chinese foie gras will also face headwinds in America as animal-rights activists continue fighting to get the duck and goose liver banned.
    — Jeremy Repanich, Robb Report, 13 July 2026
  • The scribe carefully inscribed each line with a quill made from a goose feather, while their other hand wielded an erasing knife used to sharpen the quill and scrape away any mistakes.
    — Literary Hub, Literary Hub, 6 July 2026
Definition of goose
Noun
  • One experiment, conducted in England, looked at how people understand the diminishment of ordinary bird species like the common cuckoo and the house sparrow.
    — Literary Hub, Literary Hub, 15 July 2026
  • My favorite depictions of this city know its real history is too cuckoo to capture sincerely; straight reenactments make the production of 35mm masterpieces look as piddly as Shrinky Dinks.
    — Amy Nicholson, Los Angeles Times, 1 July 2026
Definition of cuckoo
Noun
  • Winnie, on the other hand, is a flibbertigibbet of stream-of-consciousness.
    — Han Ong, New Yorker, 22 June 2025
  • Projects about Monroe have handled her personal life to varying degrees of success, often leaning into her flibbertigibbet persona, her struggles with addiction, and the paradox of her oozing sexuality and her little girl brokenness.
    — Maureen Lee Lenker, EW.com, 24 Jan. 2023
Definition of flibbertigibbet
Noun
  • There’s a tramp, a ditz, a bad boss, a hippie, a by-the-book good girl.
    — Emily Nussbaum, New Yorker, 2 Apr. 2026
  • 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
Definition of ditz
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.

Browse Nearby Words

rattle
rattlebrain
rattlebrains
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Cite this Entry

“Rattlebrain.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/rattlebrain. Accessed 18 Jul. 2026.

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