An Etymological Dictionary of the German Language/Ziel
Ziel, n., ‘limit, aim, goal,’ from the equiv. MidHG. and OHG. zil, n. Allied to Goth. tils, gatils, ‘suitable, fit,’ and gatilôn, ‘to aim at, attain,’ OHG. zilôn, ‘to make haste,’ AS. tilian, ‘to be zealous, till' (E. to till), Du. telen, ‘to produce, create,’ OSax. tilian, ‘to attain.’ To the Goth. adj. tila-, ‘suitable,’ the Scand. prep. til (whence E. till) belongs. Hence the primary meaning of the cognates is ‘that which is fixed, definite,’ so that it is possible to connect them with the Teut. root tī̆ in Zeile and Zeit.