magnetic tape

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A plastic tape coated with iron oxide for use in magnetic recording.

from the GNU version of the Collaborative International Dictionary of English.

• noun A long thin plastic ribbon coated with iron oxide or other ferromagnetic material, used to record audio or video signals digital data in the form of small magnetized regions on the tape; it is a common digital data storage medium for computer information.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun A type of (usually) acrylic tape with a fine coating of magnetically sensitive material on one side, used for recording audio and other data.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun memory device consisting of a long thin plastic strip coated with iron oxide; used to record audio or video signals or to store computer information