• WordNet 3.6
    • n sesamoid any of several small round bones formed in a tendon where it passes over a joint
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Webster's Revised Unabridged Dictionary
    • n Sesamoid (Anat) A sesamoid bone or cartilage.
    • Sesamoid (Anat) Of or pertaining to the sesamoid bones or cartilages; sesamoidal.
    • Sesamoid Resembling in shape the seeds of sesame.
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Century Dictionary and Cyclopedia
    • sesamoid Having the shape of a grain of sesame: especially applied in anatomy to small independent osseous or cartilaginous bodies occurring in tendinous structures.
    • n sesamoid In anatomy, a bone developed in the tendon of a muscle at or near a joint; a scleroskel-etal ossification, usually of a nodular shape. The largest sesamoid of the human body is the patella or kneepan. Smaller sesamoids, in pairs, are normally developed in the metacarpophalangeal and metatarso-phalangeal joints of the inner digits (thumb and great toe), and in the black races of men, and many other animals, at these joints of all the digits. Sesamoids may be developed at any joint, as the shoulder-joint of some birds. The so-called navicular bone of the horse's foot is a sesamoid. See cuts under Artiodactyla, hand, hoof, knee-joint, Perisso-dactyla, pisiform, scapholunar, and solidungulate.
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Chambers's Twentieth Century Dictionary
    • adjs Sesamoid denoting certain small bones found in the substance of the tendons at the articulations of the great toes, and in other parts of the body
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Webster's Revised Unabridged Dictionary
Gr. like sesame; sesame + e'i^dos form: cf. F. sésamoïde,
Chambers's Twentieth Century Dictionary


In literature:

Near the fetlock, at the level of the sesamoids, the internal plantar nerve ends in several digital branches.
"Diseases of the Horse's Foot" by Harry Caulton Reeks
The inhibitory apparatus of the fetlock joint is materially reinforced by the proximal sesamoid bones.
"Lameness of the Horse" by John Victor Lacroix
"Special Report on Diseases of the Horse" by United States Department of Agriculture
A sesamoid bone exists in the tendon of the triceps muscle.
"Encyclopaedia Britannica, 11th Edition, Volume 6, Slice 2" by Various
A Sesamoid bone, or a Wormian, we call, And now we may rest, for we've told them all.
"Mother Truth's Melodies" by Mrs. E. P. Miller
At the level of each metacarpo-phalangeal articulation are two sesamoid bones.
"Artistic Anatomy of Animals" by Édouard Cuyer
Even the sesamoid bones, attached behind to the toes, are two in number instead of four.
"The Cambridge Natural History, Vol X., Mammalia" by Frank Evers Beddard
A single wire passes through the phalanges of each digit, and two sesamoids are fastened on by a single wire.
"Taxidermy and Zoological Collecting" by William T. Hornaday

In news:

We discuss some of the more commonly symptomatic bones, namely the os acromiale, os styloideum, metacarpal and hallux sesamoids , patella, os trigonum, os calcaneus secundarius, accessory navicular, os peroneum, and os intermetatarseum.
The authors describe a spectrum of accessory ossicle and sesamoid pathology and suggest appropriate imaging modalities.