as and when vs whilom

as and when

conj

  • as soon as 

whilom

conj

  • Up to the time that; till, until. 

  • During the same time that; while. 

adv

  • At some time in the past; formerly, once upon a time. 

adj

  • At some time in the past; former, sometime. 

How often have the words as and when and whilom occurred in a corpus of books? (source: Google Ngram Viewer )