D defs.my
Entry 1 sense Webster, 1913

Portass

· Por·tass · IPA /ˈpɔː(ɹ)təs/
01 n. A breviary; a prayer book.
  1. 1.
    A breviary; a prayer book.[Obs.]
    “By God and by this porthors I you swear.” Chaucer.