D defs.my
Entry 1 sense Webster, 1913

Stand-by

/(stănd"bī`)/ · Stand·-by · IPA /stˈændbˌaɪ/
01 n. One who, or that which, stands by one in need; something upon which one relies for constant use or in an emergency.
  1. 1.
    One who, or that which, stands by one in need; something upon which one relies for constant use or in an emergency.