Erstwhile and Sooner

Erstwhile adjective - Having been such at some previous time.

Sooner and erstwhile are semantically related in time topic. In some cases you can use "Sooner" instead an adjective "Erstwhile", when it comes to topics like before, earlier.

Sooner noun - A native or resident of Oklahoma.

Erstwhile and sooner are semantically related in earlier topic. Sometimes you can use "Erstwhile" instead an adjective "Sooner".