- eu-good, well
- eustasyA worldwide change in sea level, especially one caused by melting ice or tectonic activity.
- eutaxyGood or established order or arrangement.
- eutherianBelonging or pertaining to the group Eutheria, comprising the mammals more closely related to animals like humans and rodents than to marsupials.
- euthymiaA normal, nondepressed, reasonably positive mood; serenity.