Darn a sock or sweater
Word Smith: Darn
“Darn,” said the student. “It’s safer around teachers, than DAMN! They get all wigged out about that word.” I challenged the student to tell me what DARN means. He looked at me quizzically. “What do you mean? It is just an acceptable way to not say a cuss word.”
I had some explaining to do…
As Web Dictionaries define: To darn is to stitch up a small hole in a piece of clothing. Instead of throwing your worn-out socks away, you can just darn the holes in their toes.
When you darn your socks or sweaters, you use a needle and thread to close small holes in the woven fabric. There’s even a specific stitch known as a “darning stitch,” in which you first weave the thread with the grain of the fabric, and then fill in the other “woven” direction. The result is a sturdy patch made only of thread. Darn comes from the Middle French word darner, “to mend.” [1]
Primary Meanings of darn
3. something of little value
- Type of: ineptitude, worthlessness
-
having no qualities that would render it valuable [2]
You have to go to the Urban Dictionary to find the word darn as a substitute for the word, damn:
- A commonly used substitute for ‘Damn,’ in craptacular American animated series.
- A giant flaming comet speeds towards the archvillian of some cartoon, obviously going to kill or severely injure him.
- Villian: “Oh Darn It!” [3]

References:
[1] http://www.dictionary.com/browse/darn
[2] http://www.yourdictionary.com/darn
[3] http://www.urbandictionary.com/define.php?term=Darn