serpent a large snake; a dragon or other mythical snake-like reptile. The word is recorded from Middle English, and comes via Old French from Latin serpent- ‘creeping’.

In proverbial and allusive reference, a serpent is taken as the type of cunning, treachery, and malignancy. The figure of a serpent with its tail in its mouth is a symbol of eternity.

In the Bible, the Serpent is a special designation of Satan, as in Genesis 3:1.
brazen serpent the figure of a brass serpent on a pole; with reference to the story in Numbers ch. 21, in which, when the people of Israel were punished by ‘fiery serpents’, Moses was told by God to mount a serpent of brass on a pole. If anyone who had been bitten by a snake looked at this, they would be healed.

See also Midgard's serpent, plumed serpent at plume, rainbow serpent.

ser·pent / ˈsərpənt/ • n. 1. chiefly poetic/lit. a large snake. ∎  (the Serpent) a biblical name for Satan (see Gen. 3, Rev. 20). ∎  a dragon or other mythical snakelike reptile. ∎ fig. a sly or treacherous person, esp. one who exploits a position of trust in order to betray it.2. hist. a bass wind instrument made of leather-covered wood in three U-shaped turns, with a cup-shaped mouthpiece and few keys. It was played in military and church bands from the 17th to 19th centuries.

serpent.
1. In Classical architecture, an emblem of healing, wisdom, and the Messenger (Hermes, St John, etc.), so part of the winged baton or caduceus.

2. Arranged in a circle, with tail in mouth, a serpent suggests immortality (see ouroboros).

serpent scaly limbless reptile, snake XIV; wind instrument of wood shaped with three U-shaped turns XVIII. — (O)F. serpent :- L. serpēns, -ent-, sb. use of prp. of serpere creep, cogn. with Gr. hérpein, Skr. sárpati; see -ENT.
So serpentine XIV. — (O)F. — late L.; see -INE1.

serpent. Obsolete bass member of cornett family, 8′ long and roughly S-shaped, hence the name. Made of wood, sometimes of metal; had 6 fingerholes and sometimes keys. First introduced in Fr. towards end of 16th cent., where it was used in church to double male vv. Became popular military-band instr. and was in use in Eng. church bands to mid-19th cent. (mentioned by Thomas Hardy).