elucidate vs mean to say

elucidate

verb
  • To make clear; to clarify; to shed light upon. 

mean to say

verb
  • To imply or intend to convey with one's words; used to correct or clarify one's previous utterance, or to seek such clarification. 

How often have the words elucidate and mean to say occurred in a corpus of books? (source: Google Ngram Viewer )