unknown number

plural unknown numbers

1. A phone number that is unfamiliar to the recipient.

   Just then Tanvi received a call from the same unknown number.

   2014, Nishigandha omanwar, Wrong Number to Right Person, Partridge Publishing, →ISBN

   2 more examples

   Kelly looked at her phone. This unknown number keep coming up. Answer it.

   2012, Kevin Johnson, Work Your Mind and Not Your Behind, Xlibris Corporation, →ISBN, page 16

   Minutes later, her phone rang. Hoping it was Nathan, she quickly checked the caller ID. Unknown number. Jessica closed her eyes. The ringing stopped but immediately started again. She checked the missed call—same unknown number.

   2014, Lutishia Lovely, The Perfect Deception, Kensington Books, →ISBN

2. A phone number that is hidden from the recipient.

   The voice on the phone sounds familiar, but the incoming call on my phone reads “ unknown.” […] And why are you calling me from an unknown number?”

   2011, Kimberly Maryie Enterprises, I Love Cash, Xlibris Corporation, →ISBN, page 330

3. Used other than figuratively or idiomatically: see unknown, number.