hostilely

This adverb describes actions performed with an overt sense of enmity or aggression. It is typically used to modify verbs of communication, perception, or physical stance, such as staring, reacting, or speaking, to signal a lack of warmth or a presence of active antagonism.

In terms of register, it is more formal than saying someone acted "meanly" or "angrily." It suggests a strategic or deep-seated opposition rather than a momentary outburst of temper. Because it is an adverb of manner, it is frequently positioned after the verb it modifies to emphasize the emotional quality of the action.