1) Celtic boy name 
[crater] This is a lava-flooded crater remnant with only low rim segments surviving to the east and west. There is a break in the rim to the south and a wider break to the northwest of the crater. The crater interior is nearly level, and mark only by a few low rises in the surface. A pair of small craterlets are attached to the exterior of ...
1902–74, U.S. physicist.