\In"board`\, a. & adv.
1. (Naut.) Inside the line of a vessel's bulwarks or hull;
   the opposite of outboard; as, an inboard cargo; haul the
   boom inboard.

2. (Mech.) From without inward; toward the inside; as, the
   inboard stroke of a steam engine piston, the inward or
   return stroke.