Groundwater is in the ground, not in lakes or rivers.

ground antennae are those antennae which are permanently inserted and cannot emit out from your gand

Ground tying means placing a picket into the ground and tying the horse to it. Ground tying is usually used by cowboys. It is more safer to tie at least even with the horse's head because the horse will catch it's leg in the rope if not careful.

A 200 amp service panel will require a # 4 bare copper ground wire.

I believe ground state menas in its noble gas form therefor all elements in period 2 such as nitrogen have a ground state of He