Khloe Kardashian has made a HUGE decision -- she's dropped Lamar Odom ... or at least his last name ... from her Twitter account.
Khloe's account used to be labeled Khloe Kardashian Odom, but now when she tweets ... it only shows up as Khloe.
It can't be a coincidence -- today is her and Lamar's 4th wedding anniversary. Khloe also dropped "Odom" from her Instagram account last week.
As we reported ... Lamar came back to L.A. late Wednesday night after a crack binge in Palm Springs with friends and two women.
Even though Lamar has big plans about what he'd like to do for the anniversary ... we're told it's not reciprocal