Yes. It can also be an adjective meaning threatening.
The word 'menacing' is a noun form, a gerund, the present participle of the verb to menace.The word menace is a noun form, a word for a possible danger; a threat; an act of threatening.The noun forms for the verb to menace are menacer (one who menaces) and the gerund, menacing.
The word menace can be used as a noun or verb. Menacing literally means to cause harm or malace to another. Synonyms include threaten, risk, and danger.
In your sentence, the word 'grumbling' is the main verb('was' is the auxiliary verb).
The word menace is a noun. The plural is menaces.
Threat is a noun. The verb form is threaten.He made a threat that he would throw out her Beanie Baby collection.She threatened to break his golf clubs.
"He looked at me with menacing eyes." "The menacing wolf bared his teeth at me snarling."
I was menacing to the store/back home
The menacing figure loomed in the shadows, sending shivers down my spine.
The menacing sky reflected Todd's mood; dark and unpleasant.
Sentence for menacing in the 5th degree in colorado
The punishment for menacing in NYS depends with the type of degree. Second degree menacing in NYS includes a maximum punishment of one year in jail and a fine of $1000.
The girl wore a menacing expression on her face.