From Black's Law Dictionary:
A search warrant is an order, in writing, issued by a justice or other magistrate, in the name of the state, directed to a sheriff, constable, or other officer, authorizing him to search for and seize any property that constitutes evidence of the commission of a crime, contraband, the fruits of crime, or things otherwise criminally possessed; or, property designed or intended for use or which is or has been used as the means of committing a crime. A warrant may be issued upon an affidavit or sworn oral testimony. Fed.R.Crim.P. 41; 18 USCA §3101 et seq.
The Fourth Amendment to U.S. Constitution provides that "no warrants shall issue, but upon probable cause, supported by oath or affirmation, and particularly describing the place to be searched, and the persons or things to be seized." See also Anticipatory search warrant; Blanket search warrant; Exclusionary Rule; Exigent circumstances; Probable cause; Search.
General search warrant. A "general warrant" for search is one which fails to sufficiently specify place or person to be searched or things to be seized and is illegal (under Fourth Amendment) as authorizing random or blanket search in discretion of police. Frey v State, 3 Md.App. 38, 237 A.2d 774, 779, 780.
Search without warrant. A search without a warrant but incidental to an arrest is permitted if it does not extend beyond the person of the accused and the area into which the accused might reach in order to grab a weapon or other evidentiary items. Chimel v California, 395 U.S. 752, 89 S.Ct. 2034, 23 L.Ed.2d 685. See also Search incident to arrest; Stop and frisk.