What is "to drop astern"

Astern \A*stern"\, adv. [Pref. a- + stern.] (Naut.)

1. In or at the hinder part of a ship; toward the hinder part, or stern; backward; as, to go astern.

2. Behind a ship; in the rear. ``A gale of wind right astern.''
   --De Foe. ``Left this strait astern.''
   --Drake.

   To bake astern, to go stern foremost.

   To be astern of the reckoning, to be behind the position given by the reckoning.

   To drop astern, to fall or be left behind.

   To go astern, to go backward, as from the action of currents or winds.

Drop \Drop\, v. i.

1. To fall in drops.

   The kindly dew drops from the higher tree, And wets the little plants that lowly dwell.
   --Spenser.

2. To fall, in general, literally or figuratively; as, ripe fruit drops from a tree; wise words drop from the lips.

   Mutilations of which the meaning has dropped out of memory.
   --H. Spencer.

   When the sound of dropping nuts is heard.
   --Bryant.

3. To let drops fall; to discharge itself in drops.

   The heavens . . . dropped at the presence of God.
   --Ps. lxviii. 8.

4. To fall dead, or to fall in death; as, dropping like flies.

   Nothing, says Seneca, so soon reconciles us to the thoughts of our own death, as the prospect of one friend after another dropping round us.
   --Digby.

5. To come to an end; to cease; to pass out of mind; as, the affair dropped.
   --Pope.

6. To come unexpectedly; -- with in or into; as, my old friend dropped in a moment.
   --Steele.

   Takes care to drop in when he thinks you are just seated.
   --Spectator.

7. To fall or be depressed; to lower; as, the point of the spear dropped a little.

8. To fall short of a mark. [R.]

   Often it drops or overshoots by the disproportion of distance.
   --Collier.

9. To be deep in extent; to descend perpendicularly; as, her main topsail drops seventeen yards.

   To drop astern (Naut.), to go astern of another vessel; to be left behind; to slacken the speed of a vessel so as to fall behind and to let another pass a head.

   To drop down (Naut.), to sail, row, or move down a river, or toward the sea.

   To drop off, to fall asleep gently; also, to die. [Colloq.]