Please don't call us "single." We're just "readily available."

So said Catherine Lin, who is hesitating whether to celebrate Singles' Day on Saturday.

Only two or three years ago on Singles' Day, she was happy and going to parties with single friends. Now most of her single friends have found partners, but she has not.

At the party Lin attended last year, there were only two other women. "We couldn't help feeling out of place," she said.

The three women vowed they would be married before the next Singles' Day. None of them succeeded. "That day has been like the Sword of Damocles over my head for the past year," Lin said.

Every year as Singles' Day approaches, thousands of college students and young working people post messages on how they'll spend the day on bulletin board websites such as www.xici.net and www.tianya.cn.

Singles' Day is, of course, not an official celebration in China. Neither the government nor any non-governmental organization has named it such. No one can say, either, exactly where and when it was first celebrated. But it's apparent that November 11 was chosen because the date, when written down in Arabic numerals, looks like four single people standing together.

There are stories that it originated on Chinese campuses at the end of last century, when college students celebrated being single with a little self-mockery. But now some Chinese have given it a classical Roman origin, saying the day honours a respectable monk during the rule of Claudius, the Roman emperor from AD 41 to 54.

According to the legend, Claudius forbade weddings so that more young people could be sent to his wars, but the unnamed monk defied his order and held weddings for lovers. He was thrown into prison and finally tortured to death on November 11.

Those who accept this version believe that, ironically, they choose to be single because of their high expectation for love.

"I can change boyfriends at the speed of changing clothes if I want to," Lin said. "I'm simply waiting for Mr Right."

Lin is a prime example of those urban young people who are leading the trend of adults remaining single in China, according to Wang Zhenyu, researcher at the Institute of Sociology, Chinese Academy of Social Sciences. "They are not like their parents," she said. "They are financially capable, and when they want to find a spouse, they are looking for more spiritual happiness than older generations did."

What's more, the current trend towards remaining single seems to be the third since New China was founded in 1949, according to Hao Maishou, sociologist at the Tianjin Academy of Social Sciences. And all seem to reflect transitions in Chinese society.

In the first wave, the nation had a record-high divorce rate after its first marriage law took effect in May 1950. An unexpectedly large number of people who got married during the War of Resistance Against Japanese Aggression (1937-45) then divorced when peace arrived.

In the second, most of the 20 million urban men and women who had gone to work in "the vast countryside" returned to cities with the end of the "cultural revolution" (1966-76), and a large number of them were not married.

In this apparent third wave, those who are involved are not willing to remain single, but they are even less willing to marry just to give in to society's demand. For them, Singles' Day has become the best time to demonstrate their stance on love and marriage.

"Believe me, no man of decent character will randomly find a girl to spend the day with," said William Ma, a 37-year-old art dealer who is still unmarried. "The lonely guys prefer to get together and have some beer, as I will."