Cilias, also known as cilia, are the hair-like structures that are found on the surface of cells lining various organs in our body. These microscopic structures play vital roles in various physiological processes such as movement, sensing, and immunity. There are several synonyms for the word cilias which include hair-like structures, motile cilia, flagella, vibrissae, respiratory cilia, and sensory cilia. These terms are used depending on the type of cilia, its location and function. For instance, motile cilia are responsible for movement and are found in the respiratory tract while sensory cilia are involved in sensing and are located in the nose and ears.