Yes, indeed! It is not wings, or beaks, or the ability to lay eggs that make a bird a bird. Some mammals lay eggs, and have beaks (like the duck-billed platypus), and some others can fly (like the bat). Reptiles like snakes and crocodiles also lay eggs.
However, it is feathers that differentiate a bird from other creatures. Birds are the only creatures that possess feathers.
Picture credit: google