variants or less commonly C-post
plural C-pillars also C-posts
: either one of two support posts that connect a vehicle's roof to its body at the rear of the rear door in a four-door vehicle or at the rear of a two-door vehicle
The 2¹/₂-in.-shorter hood, the stretched out C-pillar and the elevation of the trunk … Don Chaikin, Popular Mechanics, October 1999

Word History

First Known Use

1960, in the meaning defined above

Time Traveler
The first known use of C-pillar was in 1960

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Cite this Entry

“C-pillar.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/C-pillar. Accessed 29 Mar. 2025.

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