expansion in WordNet English dictionary

1. a discussion that provides additional information
   expansion  enlargement  elaboration 
   
2. the act of increasing (something) in size or volume or quantity or scope
   expansion  enlargement 
   
3. adding information or detail
   expansion  expanding upon 
   
4. a function expressed as a sum or product of terms
   "the expansion of (a+b)^2 is a^2 + 2ab + b^2"
   expansion