Hallux flexus may be defined as a progressive diminution of the normal range of extension at the metatarso-phalangeal, or, more rarely, at the inter-phalangeal joint of the great toe. It is unassociated with any disease of the bones, cartilages, or synovial membrane of the articulation, and originates only during the period of active growth. It is, in fact, a “hammer great toe,” and it will be found strictly analogous to the disease just described, occurring under the same conditions and affecting the corresponding articulations.[12] The name proposed by Mr. Davies-Colley has been objected to on more grounds than one. In the first place, there is perhaps a lack of soundness in the pedigree of the word “hallux.” It is a rather modern addition to anatomical nomenclature, and its sanction in classical literature is very dubious. In Plautus there is an expression “hallex viri,” implying a little man, a “thumbling,” and the words “hallex,” “allex,” and “hallux” have been used by other writers with a somewhat questionable signification for the great toe. A purist might indeed be justified in opposing the adoption of either “hallex” or “hallux,” and especially the latter; but the convenience attached to a distinctive name for the great toe in place of that of “pollex,” which is applied also to the thumb, is so great that we are not tempted to be hypercritical on philological grounds. A more serious objection has been raised against the adjective “flexus,” because in the majority of cases the toe is not actually in the position of flexion; but the term “flexion” may be applied in the sense of movement as well as in that of position; and although the great toe in hallux flexus may not reach the position of flexion, it has passed through the motion of flexion before it has attained the line of direction in which it is found in the disease.