Wiktionary
designingly
adv. With sinister designs; insidiously.
Usage examples of "designingly".
Further, Nataly put on, rather cravenly an air, of distress, or she half designingly permitted her trouble to be seen, by way of affecting her girl's recollection when the confession was to come, that Nesta might then understand her to have been restrained from speaking, not evasive of her duty.