From Longman Dictionary of Contemporary Englishsafety pinˈsafety pin noun [countable] 
DHHa metal pin for fastening things together. The point of the pin fits into a cover so that it cannot hurt you.
DHHa metal pin for fastening things together. The point of the pin fits into a cover so that it cannot hurt you.Examples from the Corpus
safety pin• I love those ones where there's a piece of cloth just with a safety pin or something like that.• The maroon dress was neatly folded, and the coral necklace carefully pinned to the bodice with a large safety pin.• Heating an implement made of a straightened safety pin, he speared the bugs, then brought them to the candle flame.• Later the gadget acquired a popular name - the safety pin - and made some one else very rich. 