Meaning

noun (genetics) the genetic variation within a population that natural selection can operate on

noun (chemistry) the existence of different kinds of crystal of the same chemical compound

noun (biology) the existence of two or more forms of individuals within the same animal species (independent of sex differences)

origin* (object-oriented programming) Coined by British computer scientist Christopher Strachey in 1967. By surface analysis, poly- + -morphism.

Etymology from Wiktionary, CC BY-SA 3.0