Yield curve inversion which lasts for at least 1 quarter has been shown to occur 1 to 2 years prior to every recession in the last 60 years. The curve inversions have not occurred outside of such a time period.
The name refers to the lowering of interest rates (yield) on longer term bond investments such that the curve “inverts” and declines as the time span increases (a 5 year investment would have higher interest than a 15 year investment for example).