To be able to understand the meaning of delisting, one has to first understand the meaning of the word “Listing”.
Listing means admission of a Company’s securities to the trading platform of a Stock Exchange, so as to provide marketability and liquidity to the security holders.
“Delisting” is totally the reverse of listing. To delist means permanent removal of securities of a listed company from a stock exchange. As a consequence of delisting, the securities of that company would no longer be tradeable at that stock exchange.
"Delisting" i.e. the said removal from a Stock Exchange, may be Voluntary (i.e. at the will of the Company) or Compulsory (i.e. out of a penal action by the Stock Exchanges, for the reason of any violations/ lapses).