What is the full form of math(s)?

"Math" (common in American English) and "Maths" (common in British English and other English-speaking countries) are both shortened forms of the word "mathematics."

• Origin of "Mathematics": The word "mathematics" comes from the ancient Greek word máth?ma (μ?θημα), which meant "that which is learned," "knowledge," or "science." Over time, its meaning narrowed to the specific discipline we know today.
• Why the "s" in "Maths"? In British English, it's common for subjects of study that are plural in form but singular in construction to be shortened with an "s" at the end if the original word ended in "ics" (e.g., physics -> physics (no change), mathematics -> maths, economics -> economics (no change), statistics -> stats). The "s" in "mathematics" originally indicated it was a collection of related disciplines (like arithmetic, geometry, etc.).
• Usage:
• Math: Primarily used in the United States and Canada.
• Maths: Primarily used in the United Kingdom, Ireland, Australia, New Zealand, and other English-speaking countries.

Both "math" and "maths" are correct shortened forms of "mathematics," with the usage depending on regional English conventions.