A person who secretly disrupts a group's activities from within the group, particularly by encouraging or committing illegal acts to discredit the group or expose them to prosecution; an instigator, troublemaker.

A secondary product; something made incidentally during the production of something else. / A side effect.

(computer hardware) The part of a computer that fetches, decodes and executes instructions; attached directly to the memory.

(grammar) A pronoun used in a question. In English, the five interrogative pronouns are what, which, who, whom, and whose (also used as relative pronouns). These require no antecedent.

A period of time when a person occupies a position only conditionally and may easily be removed for poor performance

Ownership that is not absolute and complete. / Property whose subject matter is by nature not permanent (as wild animals reduced to possession but not in captivity).

(anatomy) The cartilaginous extension of the lower sternum; the xiphisternum.

the millennium bug

(law) The legal process of verifying the legality of a will. / (law) A copy of a legally recognised and qualified will. / Clipping of probate court. / (obsolete) proof

(transitive) To establish the legality of (a will).