adj. 1. Not subject to death: immortal deities; the immortal soul. 2. Never to be forgotten; everlasting: immortal words. 3. Of or relating to immortality. 4. Biology Capable of indefinite growth or division. Used of cells in culture. n. 1. One not subject to death. 2. One whose fame is enduring. [Middle English, from Old French immortel, from Latin immortālis; see mer- in the Appendix of Indo-European roots.] im·mortal·ly adv. |
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