Cyril Pahinui, a nationally recognized Hawaiian guitarist and singer who preserved and extended the tradition of slack-key guitar, died on Nov. 17 in Honolulu. He was 68.

His death was announced by his family and by the National Endowment for the Arts, which awarded him the National Heritage Fellowship, the nation’s highest honor in folk and traditional arts, in 2017. He had been hospitalized at the Queen’s Medical Center since 2016 for a collapsed lung, pneumonia and other conditions.

Slack-key guitar — kiho’alu in Hawaiian — is a fingerpicking style that arose in the 19th century as guitars, which had been introduced to Hawaii by Mexican and Spanish cowboys, were integrated into local traditions. It was named for Hawaiian retunings of the guitar, which lowered the pitch of some strings — by loosening or slackening them — to produce consonant open chords, bringing out the instrument’s resonance.

Slack-key guitar grew into its own instrumental tradition, with soloists picking multilayered bass lines, chords and melodies. Dozens of tunings appeared in isolated local styles as Pacific islands music absorbed elements of ragtime, country, jazz and rock. Guitarists like Mr. Pahinui also accompanied their own singing, using the sweetly sustained tone, wide vibrato and rich falsetto of Hawaiian tradition.