What is the term for a court order requiring a witness to appear under penalty or pain?

The term for a court order requiring a witness to appear under penalty or pain is "subpoena." A subpoena is a legal document that commands an individual to testify before a court or produce certain evidence at a specified time and place. Failure to comply with a subpoena can result in penalties, including contempt of court, which emphasizes the seriousness of the order.

In this context, the other terms hold different meanings. A writ refers to a formal written order issued by a court with specific instructions, which could involve various legal actions beyond just summoning a witness. A summons is a document that notifies a person that they are being sued and requires them to respond to the lawsuit; it does not necessarily compel a witness to testify. Misdemeanor pertains to a category of criminal offenses, typically less serious than felonies, and does not relate to the procedural aspects of court orders concerning witnesses.