(US, slang) A police officer.

(logic) The logical principle that anything equals itself, expressed by the symbolic equation A=A.

(logic) The rule that states that not all propositions are true, the opposite of trivialism.

(colloquial, humorous) A very unpleasant mother-in-law (spouse's mother).

(computing) The observation that computing power increases as the square of the cost, e.g. a computer that costs twice as much ought to be four times as fast.

(historical) A specific kind and grade of sheepskin leather traditionally used for binding statute books and other official documents.

(humorous) A humorous adage stating that any written criticism of another writer's editing or proofreading will itself contain an error.

constitutional law

(of a person or persons) who studied law, who has a law degree

(informal) Jennifer Lawrence (born 1990), American actress.