What is "draft engine"

Draft \Draft\, a.

1. Pertaining to, or used for, drawing or pulling (as vehicles, loads, etc.). Same as Draught; as, a draft horse.

2. Relating to, or characterized by, a draft, or current of air. Same as Draught.

   Note: The forms draft and draught, in the senses above-given, are both in approved use.

   Draft box, Draft engine, Draft horse, Draft net, Draft ox, Draft tube. Same as Draught box, Draught engine, etc. See under Draught.