Appearing in LSJ (with no apparent textual or morphological justification) under the form e)pau/lios, the headword is an adjective that could theoretically modify 'road' or any of a number of other nouns. Unfortunately, it is unattested outside this entry and the derivative one in ps.-Zonaras 797.8 -- unless we read as a single word the transmitted phrase e)p' au)lei/oisi at Aristophanes, Wasps 1482 (web address 1), where the dative plural noun modified is qu/rais ('doors').