English

Alternative forms

• copper fasten
• copper-fasten

Verb

copperfasten ‎(third-person singular simple present copperfastens, present participle copperfastening, simple past and past participle copperfastened)

1. (transitive, historical) To protect the timbers [of a ship] with plates of copper secured with copper nails or bolts.
   • 1796, The Hull Advertiser, 9th July 1796:^[1]

     She is copper-fastened and copper-bottomed, and a remarkable fine ship.

2. (transitive, figuratively, Britain, Ireland) To reinforce, strengthen; to make permanent, embed.
   • 1948, The Evening Independent, November 1948:^[1]

     We had some striking examples of what happens when a guy gets so big for his britches that any pal of his is automatically a copper-fastened genius.

   • 2010 “http://www.rte.ie/news/2010/0506/courts.html Supreme Court rules on law translation]”, RTÉ News, May 6, 2010:

     This brings to an end a ten-year campaign by Pol O Murchú and other Irish language activists to copperfasten rights to have Irish language legislation made available . . . .

Usage notes

Particularly used attributively, as copper-fastened (less commonly, copperfastened).

Originally (in literal sense) an intensifier of copper-bottomed, meaning not only that the plates were copper, but the fasteners too.^[1] In meaning close to copper-bottomed, but emphasis on security and lack of ambiguity (compare nailed down), rather than on certainty and trustworthiness.^[1]

Related terms

• copper-bottomed

See also

• nail down
• pin down

References

1. 1 2 3 4 5 “Copper-bottomed”, The Phrase Finder, Gary Martin.

• “A Shipwright” “Foreign Zinc Plate” The Mechanic's Magazine, Museum, Register, Journal, and Gazette (31 May 1834) Vol.21, No.564, p.136