No girlfriend, no savings, and a poorly-paid job: Zhao Jun is typical of the "diaosi", or "losers" who have been left on the sidelines of China's decades-long economic boom.

According to a survey by Peking University and a Chinese social networking site, 72.3 percent of the diaosi are dissatisfied with their lot.

There are no official figures for this marginalised group but the term could apply to tens of millions of Chinese.

Originally from Jiangsu in eastern China, Zhao, 30, has a degree from Harbin University of Science and Technology but only earns 3,000 yuan ($500) a month working for a design company.

Eight years after he moved to the capital, he told AFP, "I live in a basement apartment in western Beijing, and pay rent of 500 yuan ($80) a month. I haven't saved anything since everything is so expensive here."

According to the survey, carried out in September, the typical diaosi -- who can be male or female -- spends less than 39 yuan on their three daily meals, uses a cheap Chinese smartphone, and is single, with 37.8 percent feeling depressed.

Of those with jobs -- 68.6 percent work overtime every day. Many seek refuge in sleep or alcohol, for many leisure time is typically spent playing video games online, while swigging cheap beer and chain-smoking cigarettes that cost $1 a pack.

Beijing-based Sinologist Renaud de Spens has given the word diaosi a prominent slot in the 2015 edition of his "Cheeky China Dictionary".

The literal translation means "penis hair" (male pubic hair), but as a slang term, de Spens wrote, "it refers to the failures, those who are both ugly and poor, those who are unmarriageable."

One Beijing diaosi nicknamed A Qi shares a room in a 1950s red brick building, of a type built to accommodate an influx of migrants from the countryside, and now often so decayed they are being demolished for redevelopment.

"Diaosi means we have no money," said A Qi, who recently quit his job at a publishing company.

"I felt depressed when I walked into the office every day and told myself I couldn't continue."

He tried to start an online business on Taobao, the Chinese equivalent of eBay, but failed again. Now disillusioned, he wants to leave the capital.

A banner in the entrance of his building reads: "Follow the Party, realise the Chinese Dream" -- a propaganda phrase popularised by President Xi Jinping.

- 'Abyss of materialism' -

In a country where the definition of success is a career, home ownership and marriage, the term diaosi was first coined pejoratively on the Internet.

It has online opposites that represent all it is to be at the top of the Chinese social pyramid: Men should be "gaofushuai" -- tall, beautiful and rich, while women should be "baifumei", -- rich, beautiful and fair skinned.

But the diaosi are now seeking to re-appropriate the word, in the same way that ethnic or sexual minorities in the West have taken possession of former insults.

The term has become a rallying point for some, symbolising their rejection of the frenzied consumerism of China's economic boom, which they can only watch from the sidelines.

"The large number of Chinese who define themselves around this concept shows how self-deprecation and a counter-culture are developing," de Spens told AFP.

"The (diaosi) affirms his pride in being neither a senior official nor a rich kid -- in the Chinese imagination, officials and rich kids don't do a damn thing.

"As such, he retains a moral integrity in the face of a society that seems to him to be plunging into an abyss of materialism."

Now, though, there is a backlash to the backlash.

In a microblog post that was forwarded tens of thousands of times, film director Feng Xiaogang decried as "brainless" those who call themselves diaosi.

Even the official Communist Party mouthpiece the People's Daily weighed in last month.

The tendency to "self-denigrate", the paper warned, should "be denounced and abandoned, because it can cause serious harm to the spirit of youth".