A fine-needle aspirator is a medical device used to collect samples from tissues or fluids in the body. It consists of a thin, hollow needle attached to a syringe, allowing healthcare professionals to extract small amounts of material for diagnostic purposes. This procedure is often performed on lumps or masses to determine if they are benign or malignant. Fine-needle aspiration is commonly used in various medical fields, including oncology and endocrinology. It is a minimally invasive technique, meaning it typically causes less discomfort and requires less recovery time compared to traditional surgical biopsies.