fretless

From fret + -less.

fretless (not comparable)

1. Of a stringed instrument, not having frets on the fingerboard.
2. Without worries.
   • 1895, Virginia Reed, Daily Cheer for All the Year, Philadelphia: G.W. Jacobs & Co., →OCLC, page 18:

     You would live longer and happier if you would only be quiet and fretless.

   • 1907 August, J. W. Foley, quotee, “The Menace of Reform”, in Texas Medical News, volume 16, number 10, Austin: Texas Medical News Publishing Co., →ISSN, page 525:

     Will the fretless world be happy or will restless nature shout / For some old-time fret or worry just to rave and kick about?

   • 1913, George Lincoln Walton, Calm Yourself, Boston: Houghton Mifflin, →OCLC, page 7:

     Is it not worth while to try and approximate, if we cannot hope to attain, the ideal of fretless, fussless, and unworrying poise?

• fretted

fretless (plural fretlesses)

1. A stringed instrument without frets on the fingerboard.
   • 2003, Jim Roberts, American Basses, San Francisco: Backbeat Books, →ISBN, page 150:

     Read's creations have covered just about all of bass-dom, from vintage-style 4-strings to 32-position fretlesses to 25-fret 8-strings tuned F♯BEADGCF.

   • 2006, Adrian Ashton, The Bass Handbook, San Francisco: Backbeat Books, →ISBN, page 47:

     No other machine can produce sounds which are so often described as 'singing', 'purring', 'humming', and 'ringing'. But this array of mellifluous notes doesn't come cheaply: even those who have mastered the fretless to moderate levels of proficiency have been obliged to spend many hundreds of hours on techniques which fretted-bass players either take for granted or simply do not require.

   • 2008, Jonathan Hererra, “ASK BP”, in Chris Jisi, editor, Bass Player Presents The Fretless Bass‎^[1], Milwaukee: Backbeat Books, →ISBN:

     Many fretlesses, especially less expensive models that mimic a fretted counterpart, have fretted-bass nut slots.