Matrix - 1) A mystical object passed on from one Autobot leader to another containing all the accumulated knowledge of the Autobots past. 2) A dimension in space where all Transformer Sparks go before being "born" and after a Transformer dies.
Maximal - A descendent of the Autobots. Generally, the Maximals are smaller than their ancestors. Maximals hold to the ideals of their ancestors holding much value in life and pursuits such as exploration of the galaxy.
Maximal Elders - A group of mysterious Maximals that rule over Cybertron and keep the Predacons at bay.
Mecannibals - Race of round, multi legged mechanical creatures who feed upon other robots.
Mega Cycle - A Cybertronian unit of time measurement that is approximately one Earth hour.
Microman - One of the Takara toy lines from which some of the first Transformers toys were borrowed.
Micromaster - Transformers whose distinguishing feature was their extremely small size. Most Micromasters were roughly the size of a human being.
Mini-con - A faction of Transformers introduced in the Armada series. Mini-Cons can be attached to larger Transformers and augment their strength as well as unlocking abilities such as hidden weapons and launching missiles.
Multiforce - A team of six Cybertrons featured in the Japanese Victory series who could each transform into a robot, combine with other team members to form a larger robot, and then all combine together to form the giant, Landcross.
My First Transformers - A line of three vehicles released in the 80's with very simple transformations. Intended
for a younger age group.