Flat Yield Curve

What Does Flat Yield Curve Mean?
A yield curve in which there is little difference between short-term and long-term rates for bonds of the same credit quality. This type of yield curve is often seen during transitions between normal and inverted curves.

Investopedia explains Flat Yield Curve
When short- and long-term bonds are offering equivalent yields, there is usually little benefit in holding the longer-term instruments - that is, the investor does not gain any excess compensation for the risks associated with holding longer-term securities. For example, a flat yield curve on U.S. Treasury would be one in which the yield on a two-year bond is 5% and the yield on a 30-year bond is 5.1%.