replacement chords

sup folks. when playing a 4 tone chord, it also has a triad lieing within. and if you keep stacking 3rds on top of eachother, you find out that theres other chords also. for ex: stacking 3rds on top of eachother.
C E G B D
in this, theres a c maj. 7 as well as a e min7. for improvising, a e min 7 arp. would sound nice over a c maj. 7 chord. but is this also a replacment chord? im not sure about replacment chords and i was wondering if any one could help me out.

I am not familiar with this concept myself (replacement). I see that CEGBD is a C Maj 9th chord, which contains the Emin7th notes (EGBD), but I have never heard of replacement chords.