A casual use of the word 'dumb' by Bollywood superstar Shah Rukh Khan landed him in a trouble here after a differently-abled girl took objection to it, prompting him to apologise and correct himself.

Khan, 45, who was speaking at a promotional event for his latest film 'RA.One', said he is keen to act in Tamil movies but only in a "dumb" character because he did not know the language and it would be difficult to deliver dialogues with perfection.

This led to a sharp reaction from an audience who said the actor should avoid using the word 'dumb' while referring to people with speech impairment.

Promptly apologising, Khan asked Jayashree for the right word to be used to refer people with speech impairment and she suggested "you can use the word mute."

The Bollywood Badshah was talking to the audience after launching the music for 'Ra One' promo here.

Khan also expressed his thanks to superstar Rajinikanth for accepting his offer to play a cameo role in Ra One, which will be simultaneously released in Tamil, Telugu and Hindi on Diwali.

He also paid a return visit to Rajinikanth, who flew to Mumbai on October 2, putting his health issue aside to shoot for Khan's dream project Ra One. Khan spent about 15 minutes with Rajnikanth.

"He was well when I spoke to him. He is very keen to start work," Khan said, replying to a question on Superstar's health. Rajnkanth will be seen in the role of 'Chitti', the robot, in the science-fiction film 'Ra.One'.