Here are some abbreviations used by stamp collectors to describe stamps for sale:
MNH mint never hinged. The stamp has original gum.
MH mint hinged
MHH mint heavy hinge
MHR mint hinge remnant not removed
MDG mint disturbed gum
MNGAI mint no gum as issued
U used
CTO canceled to order
SON cancel is complete on the front of the stamp
PC pen cancel obvious
If there are faults in the stamp, these abbreviations are typical used:
OC obliteration cancel
PP pulled perforations
SC scuff on face
F filler
ST stained
T tear
TN toning
TH thin
CR crease