Pros: 1  Works equally well in open terrain, under cover or in a gym. 2  Accurate on flat or hilly terrain and when making quick, sharp turns (e.g., when trail running or on an indoor track). 3  Lightweight design is sleeker than most GPS-enabled SDMs.
Definitions for mass extinction. Here are all the possible meanings and translations of the word mass extinction. Wiktionary(0.00 / 0 votes)Rate this definition: mass extinction(Noun) A sharp decrease in the total number of species in a relatively short period of time.
(Ä­k-stÄ­ngk'shÉn) The fact of being extinct or the process of becoming extinct. See more at background extinction, mass extinction. A progressive decrease in the strength of a conditioned response, often resulting in its elimination, because of withdrawal of a specific stimulus.