Webster's Revised Unabridged Dictionary · 1913

Thalamus

Thalamus , noun

[Latin thalamus chamber, Greek qa`lamos.]

1.
(Anatomy) A mass of nervous matter on either side of the third ventricle of the brain; -- called also optic thalamus.
2.
(a) (Botany) Same as Thallus.
(b)
(Botany) The receptacle of a flower; a torus.