This poker term is used as a matching bet by a player who wants to raise the previous bet with another one. To do this during play is to induce a call. For instance, if there a player wagers an amount in chips e.g. $20 and a raise of another $20, for a call to be made, a cost of the total of both chips is required which will amount to $40. So once the call is made, the call matches the previous or total bet which brings the first and second bets at par with the third one.
Some poker players use a call as a cheap weapon to still remain relevant in the game with a hand. When the desired amount of money to be bet upon is placed into the pot, another player who wants to call needs to match the one first made by the other player which includes a bet and a raise. This move will help to put the second player at a higher advantage than s/he was earlier and is widely used as a counter challenge.
