Related Clues:

• Roger on a ship
• Agreement from one on deck
• 'Yes, captain!'
• Shipboard affirmative
• Soldier's assent
• "Yes, captain"
• Bridge call?
• Yeoman's "yes"
• Assent on a military base
• The primate might be one of 8 down
• Is the primate all at sea yes?
• Yes, that would sound less than human on board
• It's yes for the primate, and for 7 down
• Yes, it's on board that you'll find the primate
• 1 across