Siao is a colloquial term commonly used in Singapore and Malaysia to describe someone who is crazy or silly. While the term is widely understood in Southeast Asia, there are several synonyms to describe a similar state of being. These include words like kooky, bonkers, eccentric, nutty, wacky, and zany. Other similar descriptors might include daft, offbeat, peculiar, idiosyncratic, and unconventional. Regardless of the word chosen, each describes a person who has a tendency to behave in unusual or unpredictable ways. Whether viewed positively or negatively, these synonyms capture the essence of someone who is unique, unconventional, and often entertaining.