dicky (n.)

also dickie, dickey, a diminutive form of dick, used in a variety of senses whose origin, application, and connection are more or less obscure. These include: "detached shirt front worn in place of a shirt" (1811); "a leather apron" (1874); "a donkey" (1793); "a small bird," (1851, short for dicky-bird, a nursery-word attested from 1781); "seat in a carriage on which the driver sits" (1801). For at least the garment senses Century Dictionary suggests Dutch dek "a cover, a horse-cloth."

updated on August 15, 2018

Definitions of dicky from WordNet
dicky (n.)
a small third seat in the back of an old-fashioned two-seater;
Synonyms: dickey / dickie / dickey-seat / dickie-seat / dicky-seat
dicky (n.)
a man's detachable insert (usually starched) to simulate the front of a shirt;
Synonyms: dickey / dickie / shirtfront
dicky (adj.)
(British informal) faulty; "I've got this dicky heart"- John le Carre;
Synonyms: dickey
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