Definition of plateauing:
(n) :
A largely level expanse of land at a high elevation; tableland.
(n) :
A comparatively stable level after a period of increase. (of a varying quantity)
(v) :
(intransitive) (of a varying quantity) To reach a stable level after a period of increase; to level off.
(n) :
(sports, broadcasting) A notable level of attainment or achievement.
(n) :
(drug slang) Any of several distinct, dose-dependent stages of a dextromethorphan trip.
(n) :
(dated) An ornamental dish for the table; a tray or salver.