Meaning of EXPANDER in English

 ̷ ̷ˈ ̷ ̷də(r) noun

( -s )

1. : one that expands: as

a. : an operator of a machine that expands metal tubes

b. : a tool designed to expand a boiler tube at its end so as to fit it snugly into the flue sheet

2. : any of several colloidal substances of high molecular weight (as special preparations of gelatin or dextran) used as a blood or plasma substitute in transfusion for increasing the volume of the circulating blood especially in the treatment of shock — called also extender

Webster's New International English Dictionary.      Новый международный словарь английского языка Webster.