IN (2)

In, adv. 1. 1. Not out; within; inside. In, the preposition, becomes an adverb by omission of its object, leaving it as the representative of an adverbial phrase, the context indicating what the omitted object is; as, he takes in the situation (i.e., he comprehends it in his mind); the Republicans were in (i.e., in office); in at one ear and out at the other (i.e., in or into the head); his side was in (i.e., in the turn at the bat); he came in (i.e., into the house).
Their vacation . . . falls in so pat with ours. Lamb. ☞ The sails of a vessel are said, in nautical language, to be in when they are furled, or when stowed. In certain cases in has an adjectival sense; as, the in train (i.e., the incoming train); compare up grade, down grade, undertow, afterthought, etc. 2. 2. (Law) With privilege or possession; — used to denote a holding, possession, or seisin; as, in by descent; in by purchase; in of the seisin of her husband. Burrill.
In and in breeding. See under Breeding. — In and out (Naut.), through and through; — said of a through bolt in a ship's side. Knight. — To be in, to be at home; as, Mrs. A. is in. — To come in. See under Come.