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os sesamoideum

os sesamoideum

9.9
A small round bone inside a tendon where it passes over a joint, often in hands or feet
  • noun
  • /ˌɑs ˌsɛsəˈmɔɪdiəm/
  • Specialized
translation icon : hueso sesamoideo
  • The surgeon pointed out the os sesamoideum embedded in the patient's thumb tendon.

Examples

  • Damage to the os sesamoideum can result in pain and restricted movement of the joint.

  • An X-ray of the big toe may reveal an os sesamoideum near the metatarsophalangeal joint.

  • The os sesamoideum is small.

  • Look at the os sesamoideum!

  • An X-ray of the big toe may reveal an os sesamoideum near the metatarsophalangeal joint.

  • Damage to the os sesamoideum can result in pain and restricted movement of the joint.

  • The surgeon pointed out the os sesamoideum embedded in the patient's thumb tendon.

Synonyms

sesamoid
vsos sesamoideum
  • Specialized
1 9.9

A small round bone inside a band that joins muscle to bone near a joint, like the kneecap

is the full Latin phrase rather than the shorter English name
sesamoid bone
vsos sesamoideum
  • Specialized
1 6.8

A small round bone that forms inside a tendon near a joint, like the kneecap

is a Latin anatomical term rather than the English two-word label

Surface Forms

os sesamoideum singular
os sesamoidea plural

Morphology

os + sesamoideum

The phrase literally combines 'os' (bone) with 'sesamoideum' (sesamoid-like), so a learner who knows both constituents could infer it denotes a type of bone, likely small or seed-shaped. However, the precise anatomical sense — a small round bone embedded in a tendon near a joint — is technical and relies on specialized biological usage and Latin morphology, so the full meaning is not fully predictable for a B1 learner.

Etymology

Os sesamoideum comes from Latin: os meaning 'bone' and sesamoideum meaning 'sesame seed'. These bones are small and round like a sesame seed and sit inside a tendon where it passes over a joint, so the name helps you remember they are tiny round bones in tendons near joints.