Definition of idempotence in English:
idempotence
noun ˌʌɪdɛmˈpəʊtnsʌɪˈdɛmpət(ə)nsˌɪdɛmˈpəʊtns
Computing Logic Mathematics The property of being idempotent; = idempotency.
Origin
1930s; earliest use found in American Mathematical Monthly. From idem- + potence.