1 xz is a command line tool with syntax similar to that of gzip. 2  xzdec is a decompression-only tool smaller than the full-featured xz tool. 3  A set of shell scripts (xzgrep, xzdiff, etc.) have been adapted from gzip to ease viewing, grepping, and comparing compressed files.
Epoch (astronomy), a moment in time used as a reference for the orbital elements of a celestial body. Epoch (cosmology) or cosmologic epoch, a phase in the development of the universe since the Big Bang. Epoch (geology) or geologic epoch, a span of time smaller than a period and larger than an age.
Princeton's WordNet(5.00 / 1 vote)Rate this definition: 1  era, epoch(noun) a period marked by distinctive character or reckoned from a fixed point or event. 2  era, geological era(noun) a major division of geological time; an era is usually divided into two or more periods.