Stealthily is an adverb. The ending "-ly" gives a strong indication of its part of speech.
quickly and quietly
part of speech
Adjective
What part of speech is thaw
The part of speech for oscillate is verb.
An adjective is a part of speech.
I entered the room stealthily, hoping to remain unnoticed.
He stealthily snuck into the clock tower known as Big Ben
The cat moved stealthily through the dark hallway, its steps silent and its movements careful to not disturb anything.
stealthily
heimlich
In a stealthy manner.
secretly, stealthily,
part of speech
The part of speech for this particular word is a noun.
what part of speech is beneath
adverb
what part of speech is work