undie

From undies.

• IPA^(key): /ˈʌndi/

undie (plural undies)

1. (informal, often attributive) underwear
   • November 1999, Derek de Koff, "Portrait of a Fetishist", Out, page 70:

     Here are a few pointers from an undie-snatching master.

   • November 2004, Lian Dolan, "Chaos Chronicles", Working Mother, page 98:

     Add an undie stop to the list.

   • 2006, Upamanyu Chatterjee, Weight Loss, page 348:

     Pick up the baby’s vest off the floor and put it on as an undie.

From undercover.

undie (plural undies)

1. (informal) a spy, undercover agent
   • 2016, ASAP (lyrics), “Let’s Lurk”, performed by 67 ft Giggs:

     I've got mad hate for the undies
     Moving like gyal, tryna cuff me

   • 2017, “All This”, performed by Mayhem (Uptop):

     Got a mind for the undies
     I'm tryna stay far from the pigs

un- +‎ die

• IPA^(key): /ʌnˈdaɪ̯/

undie (third-person singular simple present undies, present participle undying, simple past and past participle undied)

1. hypothetically, to come back to life after having died
2. to become undead

• Udine, indue, nudie