What is alphanumeric unicode?

Question

Character encoding

As I understand alphanumeric is English letters and numbers. What about alphanumeric unicode? Are they English letters, numbers, and characters like %[email protected]#%^?

Answer 1

Context? Where did such an expression occur?
By definition, alphanumeric is alphanumeric characters. Perhaps, it means a conditional set of Unicode letters + numbers (more precisely, classes Letter and Number).
Unicode also has a separate Mathematical Alphanumeric Symbols table