Elective surgery or elective procedure (from the Latin eligere, meaning to choose) is surgery that is scheduled in advance because it does not involve a medical emergency. Semi-elective surgery is a surgery that must be done to preserve the patient`s life, but does not need to be performed immediately. By contrast, an urgent surgery is one that c....
A surgery that is optional and not required.
Surgery which is not needed immediately, i.e., one for a non-life-threatening disorder. ... (09 Oct 1997) ... 
Elective surgery is undertaken to improve the outcome of treatment, rather than as a medical necessity e.g. the removal of certain lymph glands to reduce the risk of a cancer spreading.
Elective surgery: Surgery that is subject to choice (election). The choice may be made by the patient or doctor. For example, the time when a surgical procedure is performed may be elective. The procedure is beneficial to the patient but does not need be done at a particular time. As opposed to urgent or emergency surgery.
Surgery that is medically necessary but need not be performed immediately
An operation that is not required but which an individual opts for. It is also referred to as Optional Surgery.
an operation the patient (if age 18 years old or older) or the child's parent(s) or legal guardian(s) chooses to have done, which may not be essential to continuation of quality of life. (See also optional surgery.)