Section 2(1)(b) in The Consumer Protection Act, 1986
(b)“complainant” means—(i)a consumer; or(ii)any voluntary consumer association registered under the Companies Act, 1956 (1 of 1956) or under any other law for the time being in force; or(iii)the Central Government or any State Government; or(iv)one or more consumers, where there are numerous consumers having the same interest;(v)in case of death of a consumer, his legal heir or representative;