D-pillar

noun
D-pil·​lar | \ ˈdē-ˈpi-lər How to pronounce D-pillar (audio) \
variants: or less commonly D-post \ ˈdē-​ˈpōst How to pronounce D-post (audio) \
plural D-pillars also D-posts

Definition of D-pillar

: either one of two support posts that connect a vehicle's roof to its body at the rear of a long vehicle (such as a station wagon) The wide D-pillar creates a large blind spot for lane changes and backing out of parking spots.— Mark Phelan, Detroit Free Press, 14 Mar. 2013

First Known Use of D-pillar

1979, in the meaning defined above

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