A combination of the words "instant" and "regret;" the instant regret you feel after doing something incredible stupid and rash.
Lindsay was filled with instagret after telling her boyfriend that she still sleeps with a nightlight.
by lindyjamz June 21, 2011
The regretful feeling of putting too many photos/an embarrassing photo on Instagram the morning after a big night.
"I instagret that photo I put up of me naked rolling around in my grandfathers ashes."
"Her box gap is smaller than it used to be, she'll be instagretting that photo this morning!"
"Her box gap is smaller than it used to be, she'll be instagretting that photo this morning!"
by Be Ess March 17, 2013
by Thecarefulcunnilingust January 13, 2017
Regret associated with posting an Instagram photo from the night before that you may or may not remember taking.
Boy 1: "Damn, got huge instagret this morning. Posted a pick with this girl, turns out she wasn't hot at all and everyone knows, just hit 142 likes."
Boy 2: "I liked that! Haha, she was a straight grenade."
Boy 2: "I liked that! Haha, she was a straight grenade."
by moreritz January 20, 2015