The name Jeffrey is a boy's name of German, English origin meaning "pledge of peace". Jeffrey is ranked #323 on our popularity charts and is often added to lists like English Names for Boys and discussed in our forums with posts like "Quintuplets (boys)".
From the experts:
The mostly Americanized version of Geoffrey was a trendy mid-century hit, with nickname Jeff the epitome of cool. Jeffrey entered the pop list in 1934 and was a Top 20 name from the mid-fifties to 1978.
There are lots of Jeffrey/Jeff namesakes to reference--Actors Jeff Bridges and Jeff Daniels, writers Jeffrey Archer and Jeffrey Eugenides and race car driver Jeff Gordon.