from
The Collaborative International Dictionary of English v.0.48
Tertiary \Ter"ti*a*ry\, n.; pl. {Tertiaries}.
1. (R. C. Ch.) A member of the Third Order in any monastic
system; as, the Franciscan tertiaries; the Dominican
tertiaries; the Carmelite tertiaries. See {Third Order},
under {Third}. --Addis & Arnold.
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2. (Geol.) The Tertiary era, period, or formation.
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3. (Zool.) One of the quill feathers which are borne upon the
basal joint of the wing of a bird. See Illust. of {Bird}.
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