What does the "AP" mean when attached to a name in Family Search? Example Evan Ap Williams G57B-MZ6

William Lloyd Peterson

What does the "AP" mean when attached to a name in Family Search? Example Evan Ap Williams G57B-MZ6

Julia Szent-Györgyi

"Ap" is Welsh for "son".

MandyShaw1

Until 1837 many Welsh people used naming like Rhys ap Dafydd (or Mair ferch Dafydd, merch being Welsh for girl/daughter, while mab means son). The arrival of mandated registration across E&W in 1837 forced a much disliked change to e.g. Rhys Davies (and similarly Jones, Williams, Roberts, etc.)

William Lloyd Peterson

Thank you