darn

Concise Oxford English Dictionary © 2008 Oxford University Press:
darn1

▶verb mend (knitted material) by interweaving yarn across it with a needle.

■ embroider with a large running stitch.

▶noun a place in a garment that has been darned.

– derivatives
darning noun.

– origin C17: perh. from dial. dern ‘to hide’, from OE diernan, of W. Gmc origin.

Concise Oxford English Dictionary © 2008 Oxford University Press:
darn2 (US also durn)

▶verb, adjective, & exclamation informal euphemism for damn.