holdfast

Short definition from Wiktionary

Noun

1. 1
   Something to or by which an object can be securely fastened.
2. 2
   A root-like structure that anchors aquatic sessile organisms, such as seaweed, other sessile algae, stalked crinoids, benthic cnidarians, and sponges, to the substrate.
3. 3
   Actinomycosis.
4. 4
   The aspect of a character that experiences destructive temptation.

Proper noun

1. 1
   A hamlet and civil parish (served by Longdon, Queenhill and Holdfast Parish Council) in Malvern Hills district, Worcestershire, England (OS grid ref SO853378).