[1] : The Collaborative International Dictionary of English v.0.48

mastax \mas"tax\, n. nl., fr. gr. ? mouth, jaws. zool.
      a the pharynx of a rotifer. it usually contains four
          horny pieces. the two central ones form the incus,
          against which the mallei, or lateral ones, work so as
          to crush the food.
      b the lore of a bird.
          1913 webster

Mastax >> M Words
Mastax, definition of term: Mastax
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