'two-paneled' originates from modern English compounding of 'two' and 'panel'. 'panel' in turn originates from Old French 'panel', ultimately from Latin 'pannus' meaning 'piece of cloth'.

'panel' passed from Latin 'pannus' to Medieval Latin 'panellus', then into Old French as 'panel' and Middle English as 'panel'; 'two' derives from Old English 'twā' (Proto-Germanic *twai-/ *twō). The compound 'two-paneled' formed in Modern English by combining these elements to describe objects composed of two panels.

Initially, 'panel' referred to a piece of cloth; over time it broadened to mean a distinct section or flat piece used in construction or art. Consequently, 'two-paneled' came to mean 'composed of two such sections' in modern usage.