X0

X0 may refer to:

Grammar

• X⁰, denoting a sentence component
  • Zero-level projection, in X-bar theory
  • Head (linguistics), or nucleus

Science, technology and mathematics

• SpaceShipOne flight 15P, a 2004 private spaceflight
• X/0, division by zero
• Turner syndrome, a disorder in which all or part of an X chromosome is absent
• X0 sex-determination system, as found in some insects

Vehicles

• X0, a smaller rigged version of an X1 (dinghy)
• X0, running number for N700 Series Shinkansen prototype from 2014 to 2021

See also

• XO (disambiguation)
• X00, a popular DOS-based FOSSIL driver which was commonly used in the mid 1980s to the late 1990s