Definitions for "Indium"
A rare metallic element, of atomic number 49, discovered in certain ores of zinc, by means of its characteristic spectrum of two indigo blue lines; hence, its name. In appearance it resembles zinc, being white or lead gray, soft, malleable and easily fusible, but in its chemical relation it resembles aluminium or gallium (valence +3). Symbol In. Atomic weight, 114.82.
a rare soft silvery metallic element; occurs in small quantities in sphalerite
Atomic number 49 on the Periodic Table of Elements. Indium is a silvery metal that is very soft and malleable. It has a low melting temperature and very good cyrogenic (very low temperature, well below the freezing point of water) properties. We use indium to make bumps on our substrates for flip chip bonding. (See Bump or Flip Chip Bonding above.)