There are many synonyms you can use instead of the word "gnarrs." This uncommon word is a verb that means to growl or snarl like a dog. Alternative words and phrases include snarl, growl, bark, howl, yelp, snap, grumble, rumble, murmur, or even grump. These words can be used to describe not only the growling of a dog, but also of other animals or people who may be expressing frustration or anger in a similar way. By using synonyms like these to express the same sentiment, you can add variety and nuance to your writing, while still conveying the same meaning and emotions.