A taxi driver allegedly bit off part of a man’s thumb after a group of passengers started laughing about his name, a Dublin trial has heard.

Lookman Kareem, of Glenvara Park, Knocklyon, Dublin, pleaded not to assault causing harm to Darren O’Connor and of assaulting Noelle Donohue at Rathmines on December 22nd, 2013.

Dublin Circuit Criminal Court heard Wednesday that Mr O’Connor and his girlfriend Ms Donohue were in Dublin city centre for Christmas drinks when they caught a taxi to Rathmines in the early hours of the morning.

Two of Ms Donohue’s sisters, Stacey and Helena Donohue, were also in the taxi.

Elva Duffy BL, prosecuting told the jury in her opening statement that Stacey Donohue started giggling when she noticed Mr Kareem’s first name on his taxi identification plate and the other passengers joined in.

“Look man” is a catchphrase of Stacey Donohue’s, Ms Duffy said.

Mr Kareem allegedly became verbally abusive, saying “Shut the f*** up, shut the f*** up, you Irish”, the court heard.

The prosecution alleges Mr Kareem took his identification card down and punched Noelle Donohue in the nose when she tried to grab it to make a note of it.

When the group got out of the car, Mr Kareem allegedly hit Noelle Donohue twice, before Mr O’Connor came to her aid, getting into a scuffle with the taxi driver.

Mr O’Connor told Ms Duffy Mr Kareem grabbed on to his leg. When he reached down to try and extricate his leg, he said he felt “excruciating pain” in his hand.

“The top of my thumb was gone,” he said. “I couldn’t believe the pain. I was just looking for a piece of my thumb on the ground.”

Mr O’Connor said he ran to the nearest pub to try and get ice to keep his thumb together, collapsing once on the way. He was taken to St James’s Hospital by ambulance where he underwent surgery the next day.

Mr O’Connor told the court he and his friends were not laughing at Mr Kareem’s name, but at the fact that Stacey Donohue regularly starts sentences with the phrase, “Look man...”

“We tried to say to [Mr Kareem], ‘We’re not laughing at you’,” Mr O’Connor said. “We were trying to say it was Stacey’s phrase.”

Defence barrister Conor McKenna BL put it to Mr O’Connor that he and his friends were abusive to Mr Kareem and that two of the women told him, “this is our f***ing country, we can do what we like”.

Mr McKenna alleged Mr O’Connor, along with Noelle Donohue and Helena Donohue dragged Mr Kareem out of the car and assaulted him.

“Mr Kareem did not bite your thumb,” he said.

Mr O’Connor denied these allegations.

The trial continues before Judge Patricia Ryan and a jury of ten women and two men.