Maybe I should rephrase... 
He said something like hitting a major 9th chord or something and I looked at him like what???
Can someone explain what a 9th or an 11th is? I mean, I always thought there was like, 8 notes in a scale or something...
He was probably just trying to give advice on how to "phatten" up your chords. Instead of playing basic 3-note or 7th chords, u can play 9ths, 11ths, and 13ths.
Like it was explained earlier, once u go past the scale degrees 1-7, they start over. So, in C u have:
C=8
D=9
E=10
F=11
G=12
A=13
So, let's say u playing a regular C major chord, C-E-G. U can add in the 9th to form a Cadd9 chord like this:
C-(D)-E-G
(D)-E-G-C
E-G-C-(D)
G-C-(D)-E
Or, if ur playing a dominant 7th chord, C-E-G-Bb, u can play a dominant 9th chord instead:
C-E-G-Bb-D
Check out the Gospel Music Hangout room for more help on this topic, or u can pm me.