conspiratorially

adverb
1
in a way that is connected with, or makes you think of, a conspiracy(= a secret plan to do something illegal)
توطئه‌آمیز, تبانی‌آمیز, به طور تبانی‌آمیز
2
in a way that suggests that a secret is being shared
به طور توطئه‌آمیز, دسیسه‌وار, به طور مخفیانه
‘Guess how much it was,’ she whispered conspiratorially.