oxbow vs solid ground

oxbow and solid ground both are nouns.

Word	Noun	Adjective	Verb	Adverb
oxbow	Yes	No	No	No
solid ground	Yes	No	No	No

As nouns, solid ground is a hypernym of oxbow; that is, solid ground is a word with a broader meaning than oxbow:

Other hypernyms of oxbow include dry land, earth, ground, land, terra firma.

oxbow (noun)	solid ground (noun)
a wooden framework bent in the shape of a U; its upper ends are attached to the horizontal yoke and the loop goes around the neck of an ox	the solid part of the earth's surface
a U-shaped curve in a stream
the land inside an oxbow bend in a river