combatant vs serviceman

combatant

noun
  • A person engaged in combat, often armed. 

adj
  • Involving combat. 

  • Contending; disposed to contend. 

serviceman

noun
  • A man who serves in the armed forces. 

  • A person, especially a man, employed in service and maintenance of equipment. 

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