"Seen it" is a shortened version of "Seen Your Arse". A person who has "seen it" has become suddenly irate or upset, often disproportionately, as a result of bad news or misfortune.
by #atlanticshunter September 17, 2019
i haven't seen the sun for 3 days
by shiiiiiiiiii August 31, 2021
carter is a nickname for ‘cart’ so when asking if they’ve seen carter you’re asking them if they have a cart on them
by milfs101 November 16, 2021
See those people over there? They are best friends and honestly... I aint ever seen two pretty best friends. always one of 'em always gotta be ugly
by sum_ting_wong9 January 22, 2021