Serenely is an adverb that refers to feeling calm or peaceful. Some synonyms for serenely include tranquilly, peacefully, placidly, calmly, and quietly. Other words that can be used as substitutes for serenely include still, composed, relaxed, collected, mellow, and hushed. All these synonyms carry connotations of a tranquil and placid state of mind. When one is feeling serenely, they are without any worries, stress or tension, just inner peace and calmness. Knowing these synonyms can help you to add variety to your writing and speech, giving you a range of words to choose from depending on the context or mood of your writing.