man down

verb3

1. •
   To reduce in manpower.

   • These men have gotten word that the fort we left, Ridgeway, is manning down. So we have no worries about that. — 2011
2. •
   To lose courage or cause to lose courage.

   • Ministers and a good many of their supporters worked in relays, and had so manned down the feeble and numerically small Opposition till we had not strength nor mental energy enough to resist. — 1901
3. •
   To train (a raptor or other type of bird) to become accustomed to the presence of people; to man.

   • When taken directly from the chamber, initially Mrs Woods [a sparrowhawk] showed a high level of fear but when manned down, she went on to show no aggression whatsoever. — 2014