Auxiliary (?; 106), a. [L. auxiliarius, fr. auxilium help, aid, fr. augere to increase.] Conferring aid or help; helping; aiding; assisting; subsidiary; as auxiliary troops.
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Auxiliary scales (Mus.), the scales of relative or attendant keys. See under Attendant, a. -- Auxiliary verbs (Gram.). See Auxiliary, n., 3.
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