NTOTD: Motions of a vessel afloat

[Amgine]

There are 6 types of motion of a vessel afloat, though apparently some disagreement over what are the correct terms for these moctions:

• Yaw: The rotational motion of the hull around a vertical axis (the bow and stern are the extreme points which move most.)
• Roll: The rotational motion of the hull around a fore-and-aft axis. (the masthead and the keel are the extreme points which move most.)
• Pitch: The rotational axis of the hull around an athwartships axis. (bow, masthead, stern, and keel are all in motion.)
• Surge: forward or aft acceleration of the hull.
• Scend: vertical acceleration of the hull.
• Slide or Slip: (or possibly other terms) athwartships acceleration of the hull.

Any engineers or others amongst us who can settle the dispute regarding the sideways movement of our boats?

[BilgeRat]

Don't forget "Slam or Pound". =Waves/swells cumming up under the can, causing a jar.

[GordMay]

Ship motion is generally expressed in six degrees of freedom, which can be regarded as combinations of :
three oscillations about horizontal or vertical axes :
roll, pitch, and yaw
and three linear displacements of the center of gravity:
heave, surge, and sway

Sway describes the "sliding" lateral, side-to-side motion of a ship.

Heave describes the vertical, up (scending) and down (descending) motions of the hull.

[Amgine]

That was the other description... I kept finding slip and slide (referring to solids not necessarily afloat)...