'two-peaked' originates from modern English compounding of the numeral 'two' (Old English 'twā'), and the adjective 'peaked' derived from the noun 'peak' (Middle English 'pek'), where 'two' meant '2' and 'peak' meant 'point' or 'summit'.

'peak' changed from Old English forms (related to 'pīc'/'pīk' meaning 'point') into Middle English 'pek' and later became the modern English word 'peak'; the compound form 'two-peaked' is a straightforward modern English formation combining 'two' + 'peaked'.

Initially, 'peak' referred to a point or summit; when combined in the compound 'two-peaked' the meaning became specifically 'having two summits or prominences'.