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.
Extinction is when all members of a particular group die. Most often, we use it to discuss animal species. Many fear that the tiger is headed for extinction because of development and hunting. People are still trying to figure out what caused the extinction of the dinosaurs: many think it was because of an asteroid. When people cut down rain forests, it can lead to the extinction of many species. Although extinction can be natural or unintended, the word can also mean forced, planned killing.