Definition: Acinar is a term used in medicine, which refers to a type of cell that grows from the lining of a small organ or cavity such as the nasal cavity, ear canal, or vagina. In simple terms, an acinar cell is like a balloon inside a small, hard organ. It's tiny and soft, but it has the power to grow and make its way up the wall of the organ in order to form a larger structure. It's important to note that there are many different types of acinar cells throughout the body, such as the squamous epithelium cells found in the nasal cavity, which help protect the lining from damage by bacteria and fungi. Additionally, there may be other types of acinar cells present in specific organs or tissues, depending on their function. So what does 'acinar' mean exactly? It's a term that describes a type of cell that is small in size but still able to grow and form larger structures within the body.