The word 'temporal' entered English in the fourteenth century from Latin 'temporālis' (of or pertaining to time, lasting only for a time, secular), from 'tempus' (genitive 'temporis'), meaning 'time,' 'season,' 'the right moment,' 'opportunity.' The PIE root is debated: some scholars connect it to *temp- (to stretch, to span), conceiving time as a stretched-out duration. Others link it to *ten- (to stretch), the same root that produced 'tense,' 'tension,' and 'tendon.' If correct, time is etymologically 'that which stretches' — a span extended between past and future.
Latin 'tempus' generated one of the richest word families in English. 'Temporary' (lasting only for a time — not permanent), 'contemporary' (with the same time — living or occurring at the same period), 'extemporaneous' (out of the moment — improvised, without preparation), 'tempo' (the speed or pace of music — originally 'time' in Italian), and the grammatical 'tense' (a verb form indicating time — from Old French 'tens,' from Latin 'tempus'). Each derivative explores a different aspect of time: its impermanence, its simultaneity, its spontaneity, its rhythm, and its grammatical expression.
The word 'tempest' (a violent storm) also descends from 'tempus,' through the idea of 'weather' as 'the time' or 'the season' — Latin 'tempestās' meant both 'weather' and 'storm.' 'Temperature' follows a related path: 'temperāre' meant 'to mix in proper proportions,' 'to moderate,' 'to observe the right time or measure.' Temperature is, etymologically, the proper mixture or moderation of heat and cold — a measured quality, a balanced 'timing' of thermal conditions. 'Temperament' (a person's characteristic mixture of qualities)
The distinction between 'temporal' (worldly) and 'spiritual' (otherworldly) is fundamental to medieval Christian thought. 'Temporal power' was the authority of kings and governments over earthly matters; 'spiritual power' was the authority of the Church over souls. The investiture controversy of the eleventh and twelfth centuries — the conflict between popes and emperors over who had the right to appoint bishops — was at its core a dispute about the boundary between temporal and spiritual authority. The word 'temporal' in this context
The anatomical sense — 'temporal bone,' 'temporal lobe,' 'temporal artery' — refers to the temple of the head. Latin 'tempora' (the temples) is traditionally connected to 'tempus' (time) through the observation that the temples are where hair first turns gray, visibly marking the passage of time. Whether this folk etymology is the actual origin or not, the connection between the temple and time has been noted since antiquity.
In modern neuroscience, the 'temporal lobe' of the brain is responsible for auditory processing, language comprehension, and memory — functions intimately connected to the human experience of time. The temporal lobe processes sequential information, stores memories of the past, and enables the language through which we describe temporal relationships. That the brain region most involved in our experience of time is called 'temporal' is, etymologically, either a coincidence or a vindication of the ancient association between the temple and time.