safety pin 
noun
A pin with a point that is bent back to the head and is held in a guard when closed.Stopped at a security check at the San Francisco airport by three fatigues-wearing guards concerned about a safety pin she was wearing on her sweater, Doyle was delayed for a while....
- For the 2000 Convention in Minneapolis, the staff obviously heard my 1993 pleas and switched from the ‘open’ pin to the safety pin.
- Then, a small, colored tag is affixed to each piece of clothing with a safety pin or staple, and this tag remains attached to the clothing during the entire dry-cleaning cycle.
- Michaelis constant
- Michaelis–Menten
- michaelite
- Michaelmas
- Michaelmas daisy
- Michaelmas day
- Michaelmas eve
- Michaelmas head court
- Michaelmas summer
- Michaelmas term
- michaelsonite
- Michael, St
- michelada
- Michelangelesque
- Michelangelo
- Michelin
- Michelin man
- Michelin star
- Michelin-starred
- Michelin tire man
- Michelin tyre man
- Michelozzo
- Michelsberg
- Michelson, Albert Abraham
- Michelson experiment