Question

what is displacement reaction define in one line ? with reaction​

Answer 1

This is your answer mate

Answer 2

A single-displacement reaction, is a chemical reaction in which one (or more) element(s) replaces an/other element(s) in a compound. It can be represented generically as: A + B-C → A-C + B. This will most often occur if A is more reactive than B, thus giving a more stable product

Hope this helps you