(Science: zoology) A division of arachnoidea, including the daddy longlegs or harvestman (Phalangium) and many similar kinds. They have long, slender, many-jointed legs; usually a rounded, segmented abdomen; and chelate jaws. They breathe by tracheae.
Synonym: Phalangides, Phalangidea, Phalangiida, and Opilionea.
Origin: NL, from Phalangium the daddy longlegs (see Phalangious) _ Gr. Form.