adolescent vs undergrown

adolescent

adj
  • Of, relating to, or at the age of adolescence; at the stage between being a child and an adult. 

noun
  • A person who is in adolescence; someone who has reached puberty but is not yet an adult. 

undergrown

adj
  • insufficiently grown; not having grown to a normal or suitable size. 

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