able vs unprotected

able

noun
  • The letter "A" in Navy Phonetic Alphabet. 

adj
  • Gifted with skill, intelligence, knowledge, or competence. 

  • Having the necessary powers or the needed resources to accomplish a task. 

  • Legally qualified or competent. 

  • Free from constraints preventing completion of task; permitted to; not prevented from. 

  • Capable of performing all the requisite duties; as an able seaman. 

unprotected

adj
  • Not protected; lacking defence or protection; exposed. 

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