The definition of rigid is a person or thing that is stiff, doesn't bend or doesn't move.(adjective)
See rigid in Webster's New World College Dictionary
Origin: L rigidus < rigere, to be stiff, numb < IE base *(s)rig-, cold > frigid
See rigid in American Heritage Dictionary 4
Origin: Middle English rigide
Origin: , from Latin rigidus
Origin: , from rigēre, to be stiff; see reig- in Indo-European roots.
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