Impaneling: Selecting a jury from the list of potential jurors.

Impeach: Attacking the credibility of a witness.

Independent City Subway: subdivision B-2 of the New York City Transit Authority (NYCTA) subway. 

Initial Station: The first station on each subdivision from which a train is authorized to occupy the main track. 

Injunction: A court order requiring a person to do, or to refrain from doing, a particular thing.

Intentional Infliction of Emotional Distress: Intentionally causing severe emotional distress by extreme or outrageous conduct.

Interchange Point: The point at which two or more railroads join. Traffic is passed from one road to another at interchange points. 

Interlocking Limits: The tracks between the outer opposing absolute signals of an interlocking. 

Interlocking Signals: The fixed signals of an interlocking, governing trains using interlocking limits. 

Interlocking: An arrangement of signal appliances so interconnected that their movements must succeed each other in proper sequence. It may be operated manually or automatically. 

Intermodal: Freight traffic that refers to containerization of freight for easy trans-loading to different modes of transportation. 

Interrogatories: A written set of questions sent from one party to the other during the discovery process.

IRT: Interboro Rapid Transit. This is a subdivision of the New York City Transit Authority (NYCTA) subway.