spotlessly

comparative more spotlessly · superlative most spotlessly

1. In a spotless manner.

   And the kaleidescope ^([sic]) of distinctive colours sported by the spotlessly-maintained diesels of many different railways in the great Union stations of cities like Washington and St. Louis must have some thrills even for the most die-hard steam enthusiast.

   1955 April, Cecil J. Allen, “British Locomotive Practice and Performance”, in Railway Magazine, page 261