Rhyming slang for "word". This is actually one of the simpler examples of rhyming slang, in which a rhyming word or phrase is substituted for the given word. In more involved examples, the actual rhyming syllable is dropped. (An example of that sort of thing would be "loaf" as a slang term for "head", where "loaf" is short for "loaf of bread".)
"Not a dicky bird"
A pet name for a farm horse, or for any horse used as a working animal to pull carts and the like (NSOED).
A slang term for a place to sleep; by extension, any easy task offering a lot of opportunity for being lazy (NSOED).
A fitted garment for a man, covering the upper body and worn over a shirt. A doublet has a very short stiffened little "skirt" that is meant to conceal the "points" at the waistline where the wearer's trousers are laced on (something like the eyes of a modern shoe, where the laces were part of the trousers). A doublet buttons up the front, but is sometimes tailored so that the buttons are not easily visible; the buttons might be made of anything from wood to jewels, depending on how much money the wearer is willing to spend. If a doublet has sleeves, they would be padded; the later in the sixteenth century the doublet, the more elaborate the padding.
[Elizabeth's London: Everyday Life in Elizabethan London by Liza Picard, © 2003]
While this can be used to mean "drowsy" or lazy, it's often used to mean thick.
Short for "withdrawing room", a room of a house to which ladies might withdraw, e.g., if the gentlemen at a dinner party have a males-only session of port and cigars after dinner. The use of such a room is not normally restricted to ladies, however.