Units of time

Transformers, being extraterrestrials, are often overheard stating measurements in units that are unfamiliar to humans. Further, Transformers in different universes often use different units for measurement, and sometimes even use the same unit name but define it differently. Following is a list of units of time that Cybertronians have been observed using on the MUX.

Hey, buddy. Can you share the time?

Specific unit definitions

Name	Duration	Description
Ano-cycle	Cybertronian Calendar year	Mentioned in "Devastation". It was used in context of a set period of time, rather than a relative timespan. Each Cybertronian year is ~400 days
Astrominute	60 astroseconds	Astrominutes are referenced in the Generation 1 cartoon episode "Fire in the Sky" and could be anything from actual minutes to hours. On the MUX it is a time measured in space, away from the relativity effects of planetary bodies.
Astrosecond	.498 seconds	Defined by Dreamwave's More Than Meets The Eye #8 as 1/1000th of a breem. Astroseconds as referenced in the Generation 1 cartoon seem to be much shorter, but were never defined. In particular, in "Divide and Conquer" Shockwave states that the Space bridge will materialize within 72 billion astroseconds, an interval exceeding a millennium if Dreamwave's definition is applied. Even ignoring this extreme case, astroseconds in general cartoon use appeared to be much less than one second each. Since the cartoon depiction is not a useful measure of time, in this one case we'll go with the Dreamwave canon. On the MUX it is a time measured in space, away from the relativity effects of planetary bodies.
Breem	8.3 minutes	Originally defined in the Marvel Comics.
Century	100 stellar cycles	In the Transformers Animated premiere, "Transform and Roll Out", several references are made to the Great Wars ending "centuries ago", all prior to first contact between Transformers and Earth. This is probably a case of dialogue being written for human observers rather than indicating the existence of a "Cybertronian century", but it is included here for completeness. Similarly, the history video at the very beginning of the episode refers to "millions of years", an Earth unit. It is unclear how this time should be interpreted.
Astroweek/Cyber-week	10 cycles	A measurement used in the Shattered Glass universe. It is a week of Cybertronian days (~20 hours each).
Cycle (MUX)	20 groons	Since all canon sources differ, on the MUX a cycle equals about 1 Earth Day
Deca-cycle (Animated)	10 days	In "A Fistful of Energon", Ultra Magnus calls to report that Starscream has escaped. He says that it happened "a decacycle ago", and that he would have called sooner but their Tachyon transmitter was missing. The AllSpark Almanac defines it as 10 solar cycles.
Groon	~1 hour	Roughly equivalent to an hour. In "The Magnificent Six!", Megadeath let his broken Autobot prisoners go with a neutronic blast imminent in two groons. Retelling this event to Silverbolt in 1990, Jazz described the time as two hours.
Joor	6 hours	Used idiomatically like "hour", but of unknown duration. In "The Magnificent Six!", Steamhammer had an inspection parade scheduled at 0700 joors, not long after Cybertron's lunar dawn.
Klik	1.2 minutes	Defined for use in the IDW universe by Simon Furman in a forum post. The term first appeared in the Marvel issue "City of Fear!".
Mega-cycle (MUX)	1 million days/3000 years	Not that long for a transformer =)
Megavorn (MUX)	1 million vorns (83 MILLION YEARS)	Generally used to mean "forever" the way people use "a million" to mean near-infinite ("I wouldn't date him in a million years!")
Micro-breem	One millionth of a breem	Usually used to me 'instantly' or 'right now'. (ie: I'll be there in a Micro-breem!)
Milli-cycle	1.44 minutes	1/1,000th of a day
Minicon	~1 minute	A unit of unknown duration used in the Shattered Glass universe. Judging by its usage, it may be roughly equivalent to a minute. The term first appeared in the G1 episode "City of Steel", though its usage there does not make clear if it is meant to signify a unit of time.
Nano-klik (Beast Wars)	~1 second	As with the Beast Wars cycle, this unit is on the order of a second, as defined by the series' story editors. Used similarly in IDW comics.
Orbital Cycle	~1 month	In "A Bridge Too Close, Part I", Starscream, after hearing all his clones, mutters to himself: "This is going to be a LONG orbital cycle." The AllSpark Almanac defines it as 32 solar cycles or about a month.
Orn	~20 hours	A unit of duration. It is apparently defined as "one Cybertronian lunar day". Yesterday's Heroes!
Quadricycle	4 days	A unit of duration used in the Shattered Glass universe.
Quartex	~1 Earth month	Wheeljack lamented that the energy in the conductors that he and Bumblebee had found "wouldn't last a quartex", indicating a brief duration. MTMTE pt1 The episode's original script spelled it "quartrex", but Wheeljack is audibly not pronouncing a second "R" in the finished episode.
Solar cycle (Animated)	~1 day	In "Transform and Roll Out, Part 1", Megatron says he has spent "the last four million solar cycles searching the galaxy" for the AllSpark. The parallel to Generation 1's famous "four million years" implies that this unit is meant to be year-like. In "Part 3" Starscream refers to the 50-years of searching between the battle where "he defeated Megatron" and the present as 50 solar cycles, cementing this definition. However, in "Part 2", Optimus Prime and Ratchet have an exchange in which they use "solar cycle" in a way that is a better idiomatic match for "day" than "year". Further episodes continue with the "day" definition. The AllSpark Almanac defines it as 10 megacycles, or about a day.
Stellar cycle (Beast Wars)	~1 year/~400 days	Former Orbital period from when Cybertron circled a sun. Still used As a Cybertronian "year") for as stated by Larry DiTillio in information sent to Ben Yee. DiTillio also volunteers that Cybertron's rotational period (a "day") is ~20 hours.
Sub-cycle	<1 day	A unit of time mentioned first in "Fragmentation". On the MUX it means "less than a day".
Vorn	83 years	Originally defined in the Marvel Comics, also used in Dreamwave's comics.
Decivorn	8.3 years	The New World

Notes

• Four million Earth years is the equivalent to 1333 megabytes.