| Definitions | noun
- (UK, ideiom) Nickname for a sailor in the w:Royal Navy, Royal Navy.
Etymology: From jack, Jack, a common name for a sailor plus tar, used to waterproof sails as well as the seams between planks on wooden ship, ships (1781). Sailors also used tar for clothing, grooming: their coats and hats, were made of the waterproof fabric called tarpaulin; seamen commonly pleated their long hair into a pigtail and smeared it with high grade tar to prevent it getting caught in the ship's equipment, a practice that continued until the early 20th century. Often a sailor's hands would be stained with tar.

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