A pillar

An A-pillar is a name applied by car stylists and enthusiasts to the shaft of material that supports the windshield (windscreen) on either of the windshield frame sides. By denoting this structural member as the A-pillar, and each successive vertical support in the greenhouse after a successive letter in the alphabet (B-pillar, C-pillar etc.), this naming scheme allows those interested in car design to have points of reference when discussing design elements. The terms are also used by heavy rescue vehicle teams to discuss cutting vehicles open with the jaws of life.
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