The internet company, headed by Scots technology entrepreneur Bill Dobbie, yesterday announced plans to re-name as Cupid plc - after Cupid.com, the American site it acquired for 4.4 million in September.
The name change follows a spat with Sir Stelios, who earlier this year accused EasyDate of taking advantage of the Easy brand "to obtain an undeserved commercial advantage".
He vowed to take "further action" to protect the Easy name.
EasyDate had hoped to negotiate with EasyGroup over a strategy that would allow the trading company to keep its name, but the disagreement turned sour in September when Dobbie claimed in an interview that he had not received a lawyer's letter from EasyGroup. It later emerged that correspondence was sent to Dobbie on 29 June - to which he had replied.
Dobbie yesterday made no mention of the row with EasyGroup in a company filing to the London Stock Exchange.
The statement said: "Cupid is a name with worldwide appeal and positive connotations that we believe describes the company perfectly and will provide a solid brand for us as we continue our rapid growth and geographical expansion."
However, sources close to EasyGroup said the U-turn followed several more exchanges between EasyDate and Sir Stelios's lawyers.
"There were more letters exchanged. He (Sir Stelios] was willing to go to court over it," the source said.
"Then we had a letter about a week or so ago (from EasyDate] saying they would change their name."
Sir Stelios said in a statement: "I am delighted that EasyDate has now done the right thing and changed its name so there will no longer be any confusion that EasyDate is part of the EasyGroup family.
"EasyDate's use of the Easy brand was misleading to both consumers and investors.
"I hope other companies considering misuse of the Easy brand will take a more responsible approach in the future."
Dobbie was unavailable for comment yesterday, but a spokesman for EasyDate said: "EasyDate is changing its name for a combination of reasons, including the issue with EasyGroup.
"EasyDate's lawyers and EasyGroup's lawyers liaised over the name and, after careful consideration, EasyDate felt that it was not worth wasting time, money and resources in a legal battle over a brand that is not customer-facing anyway.
"The directors would rather put all of their efforts into continuing the company's strong growth and geographical expansion, and delivering profits for shareholders."
EasyDate floated on Aim in June, becoming in the process the UK's first listed match-making company.Its shares have risen more than 80 per cent since 30 June when they were offered at an opening price of 60p per share. The stock last night closed at 110p, down 1p on the day.
Last month the firm, which owns a string of websites including DatetheUK.com and BeNaughty.com, revealed that revenues in the first nine months of 2010 had grown at more than 30 per cent per quarter.