How about stoic or stoicism. His stoic attitude in the face of his great loss led some to think that he had no real feelings.
impatient
Impatient.
To mime is to act out silently.
Yes, it is the adverb form of the adjective silent.
The word silently *is* an adverb. The adjective form is "silent."
The word is silentium.
Noisily
silently
more silently
It is neither. The word silently is an adverb, the adverb form of the adjective silent.
Silently is an adverb. Many adverbs end in the prefix -LY.
creeps