Other forms: unperturbedly
If you stay calm and unruffled most of the time, you can say you're generally unperturbed. Your cat might be unperturbed by the noise of the vacuum cleaner, while it makes your dog hide under the bed and tremble.
People who are unperturbed aren't bothered or worried. You might be unperturbed by the scary noises your old house makes at night, because you know it's just the wind. Some people are terrified of flying on airplanes, while most remain completely unperturbed, even during bumpy, turbulent flights. When you're perturbed, you're bothered, from the Latin root perturbare, "to confuse, disorder, or disturb." When you're unperturbed, you stay cool.