underframe

[ uhn-der-freym ]
/ ˈʌn dərˌfreɪm /
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noun

the lower frame on which a vehicular structure rests: the underframe of a bus.

Origin of underframe

First recorded in 1850–55; under- + frame
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

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