ac- vs allo-

ac-

prefix
  • oak. 

  • to or with. 

allo-

prefix
  • variant. 

  • isomeric; especially, of amino acids having two chiral centres, the second diastereoisomer to be discovered or synthesized 

  • a diastereomer having the same configuration on four neighboring chiral carbon atoms as carbohydrate allose 

  • nonself; nonself but of the same species. 

  • different; other. 

How often have the words ac- and allo- occurred in a corpus of books? (source: Google Ngram Viewer )