the.com/dolly

means A dolly is a small wheeled platform or trolley used to move heavy loads or, in film, to roll a camera smoothly during a shot; it's also an affectionate pet form of the name Dorothy and a child's word for a doll.

from Dolly began as a fond diminutive of "doll," which itself is a pet form of the name Dorothy — the same playful nicknaming that turned Margaret into Molly and Mary into Polly. From "a little doll," the word stretched to mean any small, useful, well-loved thing you could push or carry, and by extension the low wheeled platform that hauls cargo or glides a camera. The cloned sheep named Dolly got her name from a different joke entirely — she was grown from a mammary cell, so scientists named her after the famously curvy country singer Dolly Parton.