The sagittal plane (/ˈsædʒɪtəl/; also known as the longitudinal plane) is an anatomical plane that divides the body into right and left sections. It is perpendicular to the transverse and coronal planes. The plane may be in the center of the body and divide it into two equal parts (mid-sagittal), or away from the midline and divide it into unequal parts (para-sagittal).

The term sagittal was coined by Gerard of Cremona.

Examples of sagittal planes include:

The term sagittal derives from the Latin word sagitta, meaning "arrow". An image of an arrow piercing a body and passing from front (anterior) to back (posterior) on a parabolic trajectory with the upright bow that shot it would be one way to demonstrate the derivation of the term. Another explanation would involve the notching of the sagittal suture posteriorly by the lambdoidal suture —similar to feathers on an arrow. The Oxford English Dictionary indicates that sagittal in the sense of the sagittal suture along the vertex of the skull pre-dates other anatomical usage.