Meaning : In secrecy. Not openly.
Example :
Met secretly to discuss the invasion plans.
The children secretly went to the movies when they were supposed to be at the library.
They arranged to meet in secret.
Synonyms : in secret, on the q.t., on the qt
Meaning : Not openly. Inwardly.
Example :
They were secretly delighted at his embarrassment.
Hoped secretly she would change her mind.