In the 1880s, while studying the three-body problem, he found that there can be orbits which are nonperiodic, and yet not forever increasing nor approaching a fixed point.    From Wordnik.com.  [- Latest Popular Stories, Instablogs Community] Reference

By activating the Analysis ToolPak add-in, you add over 30 specialized finan - cial functions that run the gamut from those that calculate the accrued interest for a security paying interest periodically and only at maturity, all the way to those that calculate the internal rate of return and the net pres - ent value for a schedule of nonperiodic cash flows.    From Wordnik.com.  [Recently Uploaded Slideshows] Reference

160 decibels, or 185 decibels for "nonperiodic blast pressure.".    From Wordnik.com.  [Cocktail Party Physics] Reference

1963: Deterministic nonperiodic fl ow.    From Wordnik.com.  [The Full Feed from HuffingtonPost.com] Reference