du·ra·tion (d-rāshən, dy-)
1. Continuance or persistence in time.
2. A period of existence or persistence: sat quietly through the duration of the speech.
3. The number of years required to receive the present value of future payments, both of interest and principle, of a bond, often used as an indicator of a bond's price volatility resulting from changes in interest rates.
[Middle English duracioun, from Old French duration, from Medieval Latin dūrātiō, dūrātiōn-, from Latin dūrātus, past participle of dūrāre, to last; see deuə- in the Appendix of Indo-European roots.]
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