spiral arm
English
Noun
spiral arm (plural spiral arms)
- (astronomy) A section of a spiral galaxy that coils out from the centre.
- 1979, Douglas Adams, The Hitchhiker's Guide to the Galaxy
- Far out in the uncharted backwaters of the unfashionable end of the western spiral arm of the Galaxy lies a small unregarded yellow sun.
- 1979, Douglas Adams, The Hitchhiker's Guide to the Galaxy