A Form Barre Chords - Major 7th|
A-form - Major 7th: This isn't the only way to barre a Major Seventh chord, but it certainly is the most common and the easiest on the fingers. That note on the third string is the 7, and the fact that it's jogged out of alignment with the other two makes it much easier to finger and get the chord ringing nicely. The bass note names the chord, but remember that the bass notes for all of these A-form barre chords is on the fifth string.
Read more about the A-form family of barre chords here.