The Collaborative International Dictionary of English v.0.48:

Ostent \Os"tent\, n. [L. ostentus, ostentum, fr. ostendere (p.
   p. ostensus and ostentus) to show. See Ostensible.]
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   1. Appearance; air; mien. --Shak.
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   2. Manifestation; token; portent. --Dryden.
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            We asked of God that some ostent might clear
            Our cloudy business, who gave us sign. --Chapman.
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