SECS is an acronym for Seconds, which is a unit of time. JIFFS is an abbreviation for Jiffies, which are a unit of time equal to 1/100th of a second. INSTANTS is an alternate term for an instant, which is a very short period of time. TRICES is an abbreviation for Triseconds, which are a unit of time equal to 1/1000th of a second. All of these terms refer to very small units of time, and are used to measure the speed of computers and other electronic devices.