何とやら

Meanings

1. Adverb

   for some reason or other; somehow

2. Expression

   whatsitsname; what-you-call-it; Mr. so-and-so
3. and so on; and you know the rest

• 噂うわさをすれば何なんとやらだな。

  Speak of the devil and he is sure to appear.

• 噂うわさをすれば何なんとやら。キャシーが来きたわよ。

  Speak of the devil, here comes Kathy.