questioning vs stubborn

questioning

adj
  • Unsure of one's sexual orientation and/or gender identity. 

  • Characterized by questions, inquisitiveness, doubt, or wonder. 

noun
  • Interrogation. 

  • The action of asking questions; a survey; an inquiry. 

  • The act of challenging, wondering, and doubting. 

stubborn

adj
  • Refusing to move or to change one's opinion; obstinate; firmly resisting; persistent in doing something. 

  • Of materials: physically stiff and inflexible; not easily melted or worked. 

noun
  • Stubbornness. 

  • A disease of citrus trees characterized by stunted growth and misshapen fruit, caused by Spiroplasma citri. 

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