I-sōch’ro-nal, a.

a. [Gr. ἰσόχρονος, from ἴσος, equal, and χρόνος, time; Fr. isochrone.] Uniform in time; of equal time; performed in equal times; as, isochronal vibrations or oscillations.

Isochronal line, a line along which a heavy body descends with a uniform velocity.