Webster's English Dictionary

Enter the word to look up:

substratum

sub.stra.tum \'s*b-.stra-t-*m, -.strat-, 's*b-'\ \-*\ n or sub.stra.ta [ML, 
   fr. L, neut. of substratus, pp. of substernere to spread under] pl , fr. 
   sub- + sternere to spread - more at STREW : an underlying support : 
   FOUNDATION : as  : substance that is a permanent subject of qualities or 
   phenomena  : the material of which something is made and from which it 
   derives its s pecial qualities : a layer beneath the surface soil; specif : 
   SUBSOIL  : SUBSTRATE, SUBSTRATE  : a thin coating (as of hardened gelatin) 
   on the support of a photographi c film or plate to facilitate the adhesion 
   of the sensitive emulsion