holdfast

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.) Defn: 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.

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