Tanned means browned by the sun. Deeply tanned, tanned arms, come back tanned.
The brown is melanin produced as damage response, which is why a tan is a record of injury rather than a sign of health — the idea that it means the opposite dates from the 1920s and a change in fashion. Leather is tanned by a different process with the same name. Note tan, tanning.
1adjectivetannedBrowned by the sun.
“She came back from her beach holiday looking tanned and relaxed.”
tanned is a quality of colour.