De luxe and First-string

De luxe adjective - Elegant and sumptuous.

First-string and de luxe are semantically related. in better topic. In some cases you can use "First-string" instead an adjective phrase "De luxe".

First-string adjective - Of the very best kind.

De luxe and first-string are semantically related. Sometimes you can replace phrase "De luxe" with "First-string", this phrases are similar.