• Finnish: tarttuva
• Icelandic: fastheldinn , fastheldin , fastheldið

• Finnish: sitkeä, sinnikäs
• Icelandic: þrár , þrá , þrátt ; þolgóður , þolgóð , þolgott ; ötull , ötul , ötult

Tenacious root word tenac from greek meaning strong/determined:

Ships and boats:

• HMS Tenacious (R45), a British Royal Navy destroyer.
• RSS Tenacious (71), a Formidable class frigate of the Republic of Singapore Navy.
• USNS Tenacious (T-AGOS-17), a United States Navy Ocean Surveillance Ship.
• SV Tenacious, a British sail training ship.
• Tenacious, a racing yacht based on a design by Sparkman & Stephens and built by the Palmer Johnson yard. Winner of the 1979 Fastnet race.

Music:

• Tenacious D, an American band started by Jack Black and Kyle Gass
• Tenacious Records, a record label founded by percussionist Alphonse Mouzon.

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