- short for spiral-bound.a spiral notebook
- Astronomyshort for spiral galaxy.
verb (spirals, spiralling, spiralled; US spirals, spiraling, spiraled)
mid 16th century (as an adjective): from medieval Latin spiralis, from Latin spira 'coil' (see spire2)
Double the l when adding endings which begin with a vowel to words which end in a vowel plus l (as in travel): (spirals, spiralling, spiralled).