Del"toid (?), a. [Gr. deltoeidh`s delta-shaped; de`lta the name of the letter ei^dos form: cf. F. deltoide. See Delta.]
Shaped like the Greek (delta); delta-shaped; triangular.
Deltoid leaf Bot., a leaf in the form of a triangle with the stem inserted at the middle of the base. -- Deltoid muscle Anat., a triangular muscle in the shoulder which serves to move the arm directly upward.
© Webster 1913.