Basic Guidelines For English SpellingsREAD THESE ARTICLES
1‘the microphones had been used for secretly recording conversations’
covertly, without anyone knowing, in secret, in private, privately, in confidence, confidentially, behind closed doors, behind the scenes, behind someone's back, under cover, under the counter, discreetly, unobserved, quietly, furtively, stealthily, on the sly, on the quiet, privily, conspiratorially, clandestinely, on the side
sub rosa, in camera
informal on the q.t.
2‘I think he was secretly jealous of Bartholomew’
privately, in one's heart, in one's heart of hearts, in one's innermost thoughts
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