Big time

This American expression as in to hit the big time means to ascend the upper echelons of a pursuit or profession e.g. Hollywood stardom, fame etc and dates from the early 20th century c. 1910. A more recent usage as an adverb meaning greatly or very much so is prevalent from the late 20th century as in “I enjoyed myself big time”. In the 21st century, this seems to have gravitated towards ‘huge time’.