• WordNet 3.6
    • n Xiphosura horseshoe crabs and extinct forms
    • ***
Webster's Revised Unabridged Dictionary
    • n. pl Xiphosura See Xiphura.
    • ***
Century Dictionary and Cyclopedia
    • n xiphosura Same as Xiphisura: in this form, in Lankester's classification, brought under Arachnida as one of three orders (the other two being Eurypterina and Trilobitæ) brigaded under the name Delobranchia.
    • ***


In literature:

Xiphosura Limulus Shield Crabs {12.
"The History of Creation, Vol. II (of 2)" by Ernst Haeckel
Xiphosurae, of the grade Delobranchia or Hydropneustea.
"Encyclopaedia Britannica, 11th Edition, Volume 15, Slice 7" by Various