There's no reason to be indirect when explaining the etymology of crabwise; we'll get right to the point. As you might guess, the meaning of that word is directly related to that sidling sea creature, the crab. If you live near the shore or have visited a beach near the sea, you have probably seen crabs scuttling along, often moving sideways and not taking what humans would consider the most direct route. The modern meanings of crabwise were definitely inspired by the crab's lateral or oblique approach to getting from one place to another. The word crept into English in the mid-19th century and has been sidling into our sentences ever since.
Examples of crabwise in a Sentence
she inched crabwise out of the room, hoping no one would notice