Erythema solare and First-degree burn

Erythema solare noun - Redness of the skin caused by exposure to the rays of the sun.

First-degree burn and erythema solare are semantically related. In some cases you can use "First-degree burn" instead a noun phrase "Erythema solare".

First-degree burn noun - Burn causing redness of the skin surface.

Erythema solare and first-degree burn are semantically related. Sometimes you can replace phrase "Erythema solare" with "First-degree burn", this phrases are similar.