'To drop astern' definitions:

Definition of 'To drop astern'

From: GCIDE

Drop \Drop\, v. i.
1. To fall in drops. [1913 Webster]
The kindly dew drops from the higher tree, And wets the little plants that lowly dwell. --Spenser. [1913 Webster]
2. To fall, in general, literally or figuratively; as, ripe fruit drops from a tree; wise words drop from the lips. [1913 Webster]
Mutilations of which the meaning has dropped out of memory. --H. Spencer. [1913 Webster]
When the sound of dropping nuts is heard. --Bryant. [1913 Webster]
3. To let drops fall; to discharge itself in drops. [1913 Webster]
The heavens . . . dropped at the presence of God. --Ps. lxviii. 8. [1913 Webster]
4. To fall dead, or to fall in death; as, dropping like flies. [1913 Webster]
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. [1913 Webster]
5. To come to an end; to cease; to pass out of mind; as, the affair dropped. --Pope. [1913 Webster]
6. To come unexpectedly; -- with in or into; as, my old friend dropped in a moment. --Steele. [1913 Webster]
Takes care to drop in when he thinks you are just seated. --Spectator. [1913 Webster]
7. To fall or be depressed; to lower; as, the point of the spear dropped a little. [1913 Webster]
8. To fall short of a mark. [R.] [1913 Webster]
Often it drops or overshoots by the disproportion of distance. --Collier. [1913 Webster]
9. To be deep in extent; to descend perpendicularly; as, her main topsail drops seventeen yards. [1913 Webster]
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.] [1913 Webster]