A piece of skin and subcutaneous tissue partially detached from its site of origin but retaining a vascular pedicle which allows it to survive while being moved (often in stages) to another site.
Origin
Mid 19th century.
Definition of skin flap in US English:
skin flap
noun
A piece of skin and subcutaneous tissue partially detached from its site of origin but retaining a vascular pedicle which allows it to survive while being moved (often in stages) to another site.