From Longman Dictionary of Contemporary Englishthe operative wordthe operative wordREPEATused when you repeat a word from a previous sentence to draw attention to its importance The new system offers fast solutions. Fast being the operative word. → operative
Examples from the Corpus
the operative word• Fast, by the way, is the operative word.• I was madly - and that's the operative word - head over heels in lust.• He's a kind of amateur psychologist, and amateur is the operative word here.• Edgy is the operative word here.• The word liberty is the operative word.• There are now programs on the market that can almost read as well as humans - almost being the operative word, of course. 