pinning

verb

1. (form-of, gerund, participle, present)present participle and gerund of pin

noun

1. (countable, uncountable)The action of the verb pin in any sense.
2. (countable, uncountable)A ceremony in which a pin badge is given.

   “There were a variety of informal traditional activities that occurred in recognition of events such as birthdays, pinnings (when a member gave his fraternity pin to his girlfriend to acknowledge preengagement), and engagements.”

3. (countable, uncountable)The establishment of the definite quantum state of a particle, or of the occupation number of a system of particles