This is one of the most common question I encounter. It is also one that is very often misinterpreted due to poor translation or the actual meaning being lost in translation.
Speculative fiction is referred to as 幻想小说 (huànxiǎng xiǎoshuō). It literally means imaginative or speculative fiction. It can be divided into two broad sub-genres: science fiction 科幻 (kēhuàn) and fantasy 奇幻 (qíhuàn).
Ke refers to keji 科技 (kējì), which means technology. Kehuan is literally speculative fiction about technology.
Qihuan 奇幻 (qíhuàn)
Qihuan is literally fantastical speculative fiction. It’s the Chinese term for the fantasy genre. Wuxia is considered a sub-genre of fantasy.
The term mohuan 魔幻 (móhuàn) is sometimes used to refer specifically to fantasy fiction, especially Western ones, that has supernatural or magical elements. Mo refers to mofa 魔法 (mófǎ), which means magic.
Wuxia 武俠 (wǔxiá)
Wu means fighting or the use of force. Xia means a chivalrous person. Wuxia referred to a chivalrous person who fights. With the popularity of the genre of novels revolving around wuxia protagonists, chivalrous heroes and heroines who fight for their causes, wuxia also came to refer to these types of stories.
The common elements in wuxia stories are fictitious martial arts abilities that give the practitioners incredible abilities. They aren’t magic but they are pretty close enough given how out of the world they can get.
You will recognise wuxia in movies when you see characters flying through the air, jumping from roof to roof, or walking on water.
Xianxia 仙侠 (xiānxiá)
Xian means an immortal or celestial being. Xianxia means a chivalrous immortal or celestial being. It is a sub-genre of wuxia.
Xianxia differ from traditional wuxia where are usually no immortals or celestial beings. Celestial beings in Chinese culture can also be fairies, demons, and spirits. This sub-genre is a fusion of wuxia and Chinese mythology.
Given that Chinese mythology bear many elements of Daoism, it is common to see them in xianxia stories as well. It is also not a far-fetched to consider Classical Chinese mythology as xianxia. They just have been around and passed down generations long enough to attain mythological status.
Xuanhuan 玄幻 (xuánhuàn)
Xuan refers to (xuánxiǎng) 玄想, which means imagination or illusion. The term comes from author Huang Yi, the pioneer of the genre. He referred to his works as fantasy novels based on the imagination.
Unlike traditional fantasy/qihuan, xuanhuan is based on fantasy but combines elements from science fiction and wuxia. They could also be adaptations of movies, anime, or games similar to fan fiction.
Xuanhuan pushes the boundaries of speculative fiction by being a melting pot of the wildest fantasies. Anything the authors can imagine can be possible in these stories.
Differentiating between wuxia, xianxia, and xuanhuan
It is easy to spot xuanhuan. These stories are out of this world. You get magic and science fiction elements.
Wuxia and xianxia are more grounded within the realms of traditional fantasy novels. Between these two, you can easily tell them apart. If you see any immortals, fairies, demons or spirits, it’s xianxia.