Other forms: tranquiler; tranquilest
When a place or your state of mind is peaceful, quiet and serene, it is tranquil.
Like a pond with no ripples, tranquil means calm and placid. A pleasant state of mind, with nothing to agitate or cause anxiety, can also be considered tranquil. As you struggle through your yoga poses, the teacher might annoyingly exclaim how tranquil you should be feeling, and when you and your siblings bicker over every little thing, your parents are wishing the house were more tranquil.