[TA] the portion of a structure that lies most forward, or closest to the front surface, relative to other parts; in human anatomy, the ventral portion of a structure. see anterior part of: anterior commissure of brain; quadrangular lobule of cerebellum; central lobule of cerebellum; culmen; lateral parabranchial nucleus; diaphragmatic surface of liver; tongue; fornix of vagina. SYN: pars anterior [TA].