• Webster's Revised Unabridged Dictionary
    • Episternum (Anat) A median bone connected with the sternum, in many vertebrates; the interclavicle.
    • Episternum (Zoöl) One of the lateral pieces next to the sternum in the thorax of insects.
    • Episternum (Anat) Same as Epiplastron.
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Century Dictionary and Cyclopedia
    • n episternum In mammals, the manubrium sterni: the presternum of most authors.
    • n episternum In lower vertebrates, some presternal part. See interclavicle.
    • n episternum In entomology, the anterior one of the three sclerites into which the propleuron, the mesopleuron, and the metapleuron of an insect are severally typically divisible, lying above the sternum, below the tergum, and in front of an epimeron.
    • n episternum In Chelonia, same as epiplastron: so called by most anatomists, who have considered it an element of a sternum. See second cut under Chelonia.
    • n episternum plural In comparative anatomy, the lateral pieces of the inferior or ventral are of the somite of a crustacean.
    • n episternum In spatangoid sea-urchins, the third pair of plates on the ventral face of the posterior interradius.
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Chambers's Twentieth Century Dictionary
    • n Episternum ep-i-ster′num the interclavicle: the epiplastron: the presternum of mammals
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Webster's Revised Unabridged Dictionary
NL. See Epi-, and Sternum


In literature:

Episternum: the anterior and larger lateral thoracic sclerite between the sternum and notum.
"Explanation of Terms Used in Entomology" by John. B. Smith
In IIIA, the episternum (a) and epimeron (b) are slightly separated.
"Encyclopaedia Britannica, 11th Edition, Volume 13, Slice 4" by Various
The relations of this bone to the clavicles seem to leave no doubt that it is the equivalent of the Lacertilian interclavicle or episternum.
"The Cambridge Natural History, Vol X., Mammalia" by Frank Evers Beddard