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Webster 1913 Edition
Holdfast
Hold′fastˊ
,Noun.
1.
Something used to secure and hold in place something else, as a long flat-headed nail, a catch a hook, a clinch, a clamp, etc.; hence, a support.
“His holdfast was gone.” Bp. Montagu.
2.
(Bot.)
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.
Webster 1828 Edition
Holdfast
HOLDFAST
,Noun.