1. A wide-mouthed vessel (usually cylindrical) without handles.
2. The quantity contained in a jar; SYN. jarful.

1. To place in a jar.
2. To shock physically; SYN. shake up, bump around.

Acronym for Java Archive file. JAR files allow Java developers to efficiently deploy Java classes and their associated resources. The elements in a JAR file are compressed just as in a standard zip file. JAR files include a security mechanism and a special META-INF directory that contains administrative information about the contents of the files. Using a combination of a digital signature and the META-INF data, JAR files can be signed to ensure authenticity and security. See also .jar.
Platform-independent file format tat aggregates many files into one.

A file name extension that identifies a compressed JAR (Java Archive) file. Note: By changing the .jar extension to .zip, you can use popular extraction tools such as PKZIP or WINZIP to look at a .jar file’s contents. See also compressed file, JAR, PKZIP, .zip.