The term 'temperature-varying' is a compound word formed from 'temperature' and 'varying'. 'Temperature' originates from Latin 'temperatura', meaning 'a moderate condition', and 'varying' comes from Latin 'variare', meaning 'to change'.

'Temperature' evolved from the Latin 'temperatura' through Old French 'temperature', while 'varying' evolved from Latin 'variare' through Old French 'varier'.

Initially, 'temperature' referred to moderation in conditions, while 'varying' meant changing. Together, they describe a condition where temperature changes.