Entry 1 sense Webster, 1913 Hallowmas /(hăl"lō̇*mȧs)/ · Hal·low·mas · IPA /ˈhæloʊməs/ 01 n. The feast of All Saints, or Allhallows. 1. The feast of All Saints, or Allhallows. “To speak puling, like a beggar at Hallowmas.” — Shak.