Surgery (from the Greek: χειρουργική cheirourgikē (composed of χείρ, "hand", and ἔργον, "work"), via Latin: chirurgiae, meaning "hand work") is an ancient medical specialty that uses operative manual and instrumental techniques on a patient to investigate or treat a pathological condition such as disease or injury, to help improve bodily function or appearance or to repair unwanted ruptured areas (for example, a perforated ear drum).
An act of performing surgery may be called a "surgical procedure", "operation", or simply "surgery". In this context, the verb "operate" means to perform surgery. The adjective "surgical" means pertaining to surgery; e.g. surgical instruments or surgical nurse. The patient or subject on which the surgery is performed can be a person or an animal. A surgeon is a person who practices surgery and a surgeon's assistant is a person who practices surgical assistance. A surgical team is made up of surgeon, surgeon's assistant, anesthesia provider, circulating nurse and surgical technologist. Surgery usually spans minutes to hours, but it is typically not an ongoing or periodic type of treatment. The term "surgery" can also refer to the place where surgery is performed, or simply the office of a physician, dentist, or veterinarian.
Surgery is a technology consisting of a physical intervention on tissues.
As a general rule, a procedure is considered surgical when it involves cutting of a patient's tissues or closure of a previously sustained wound. Other procedures that do not necessarily fall under this rubric, such as angioplasty or endoscopy, may be considered surgery if they involve "common" surgical procedure or settings, such as use of a sterile environment, anesthesia, antiseptic conditions, typical surgical instruments, and suturing or stapling. All forms of surgery are considered invasive procedures; so-called "noninvasive surgery" usually refers to an excision that does not penetrate the structure being excised (e.g. laser ablation of the cornea) or to a radiosurgical procedure (e.g. irradiation of a tumor).