The senior grade of lieutenant is known as first lieutenant in the United States, and as lieutenant in the United Kingdom and the rest of the English-speaking world.

In English, lieutenant is best known as a military title, but the word is still sometimes used in its original meaning to refer to a person who acts in lieu of someone else.

Lieutenant, company grade officer, the lowest rank of commissioned officer in most armies of the world. The lieutenant normally commands a small tactical unit such as a platoon.

LIEUTENANT definition: 1. (the title of) an officer of middle rank in the armed forces: 2. (the title of) an officer of…. Learn more.

A lieutenant is a junior officer in the army, navy, or air force. The lieutenant ordered the man to stop.

lieutenant noun A person who holds a position auxiliary to another and assumes some of the superior's responsibilities:

Definition of lieutenant noun in Oxford Advanced Learner's Dictionary. Meaning, pronunciation, picture, example sentences, grammar, usage notes, synonyms and more.