Etymology: Middle English, from Old English hit — more at he
Date: before 12th century
1. that one — used as subject or direct object or indirect object of a verb or object of a preposition usually in reference to a lifeless thing <took a quick look at the house and noticed it was very old>, a plant <there is a rosebush near the fence and it is now blooming>, a person or animal whose sex is unknown or disregarded <don't know who it is>, a group of individuals or things, or an abstract entity <beauty is everywhere and it is a source of joy> — compare he, its, she, they 2. — used as subject of an impersonal verb that expresses a condition or action without reference to an agent <it is raining> 3. a. — used as anticipatory subject or object of a verb <it is necessary to repeat the whole thing> — often used to shift emphasis to a part of a statement other than the subject <it was in this city that the treaty was signed> b. — used with many verbs as a direct object with little or no meaning <footed it back to camp> 4. — used to refer to an explicit or implicit state of affairs or circumstances <how is it going> 5. a crucial or climactic point <this is it> II. noun Date: 1842 the player in a game who performs the principal action of the game (as trying to find others in hide-and-seek)
New Collegiate Dictionary. 2001.