Middle English thwerte, from the adjective thwert 'perverse, obstinate, adverse', from Old Norse thvert, neuter of thverr 'transverse', from an Indo-European root shared by Latin torquere 'to twist'.

• torch from Middle English:

  A torch in the original sense of ‘something soaked in an inflammable substance used to give light’ was often made of twisted hemp or other fibres. This is still the American meaning, and reflects the word's Latin origin, torquere ‘to twist’. Only in British English can torch describe a battery-powered electric lamp, which Americans call a flashlight. A torch song is a sad or sentimental song of unrequited love, whose name, used since the 1920s, comes from the phrase carry a torch for, ‘to love someone who does not love you in return’. The image in pass on the torch, ‘to pass on a tradition, especially one of learning or enlightenment’, is that of the runners in a relay race passing on the torch to each other, as was the custom in the ancient Greek Olympic Games. The Latin source of torch, torquere, is found in a large number of other English words. Most obviously it is the source of the engineer's torque (late 19th century), and the twisted Celtic neck-ring the torc (mid 19th century). Less obviously it is in contort (Late Middle English) ‘twist together’; distort (Late Middle English) ‘twist out of shape’; extort (early 16th century) ‘twist out of’; and retort (Late Middle English) ‘to twist back’ (the chemical apparatus gets its name from its twisted shape). Tortura ‘twisting, torment’ the Latin noun formed from the verb gives us torture and tortuous (both LME), and torment (Middle English). Thwart (Middle English) is an Old Norse word that goes back to the same Indo-European root.