acidulous vs aculeated

acidulous

adj
  • Sharp; caustic. 

  • Slightly sour; sub-acid; sourish. 

  • Containing carbonic acid. 

aculeated

adj
  • Pungent, incisive. 

  • Having a sharp point; armed with prickles. 

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