HOLDFAST
fastener, fastening, holdfast, fixing
(noun) restraint that attaches to something or holds something in place
Source: WordNet® 3.1
Etymology
Noun
holdfast (plural holdfasts)
Something to or by which an object can be securely fastened.
(biology) A root-like structure that anchors aquatic sessile organisms, such as seaweed, other sessile algae, stalked crinoids, benthic cnidarians, and sponges, to the substrate.
Hyponym: hapteron
(archaic, medicine) Actinomycosis.
Source: Wiktionary
Hold"fast`, n.
1. Something used to secure and hold in place something else, as a
long fiat-headed nail, a catch a hook, a clinch, a clamp, etc.;
hence, a support. "His holdfast was gone." Bp. Montagu.
2. (Bot.)
Definition: A conical or branching body, by which a seaweed is attached to
its support, and differing from a root in that it is not specially
absorbent of moisture.
Source: Webster’s Unabridged Dictionary 1913 Edition