whilere

From Middle English whil er, whileere [and other forms], whilom er (“some while ago or before, formerly”), from Old English hwīle ǣr, hwīlum ǣr, from hwīle (accusative singular of hwīl), hwīlum (“at some time in the past, once; sometimes”) (dative plural of hwīl (“period of time, a while”), ultimately from Proto-Indo-European *kʷyeh₁- (“to rest; peace, rest”)) + ǣr (“before”) (ultimately from Proto-Germanic *airiz (“before, earlier”)). The English word is analysable as while + ere.

来源：wiktionary