Red-brown and Reddish brown

Red-brown adjective - Of brown tinged with red.

Reddish brown and red-brown are semantically related. In some cases you can replace phrase "Reddish brown" with "Red-brown", this phrases are similar.

Reddish brown noun - A shade of brown with a tinge of red.

Red-brown and reddish brown are semantically related. You can use "Red-brown" instead an adjective phrase "Reddish brown".