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in-commūtābĭlis, e, adj., unchangeable, immutable (rare but class.): omnia verbi principia incommutabilia viderentur (opp. commutabilia), Varr. L. L. 9, § 99 Müll.: status rei publicae, * Cic. Rep. 2, 33, 57: bonum, Aug. Retract. 1, 9.
Adv.: in-commūtābĭlĭter, unchangeably, immutably, Aug. Ep. 3, 3; id. Trin. 7, 1.