Several
Definition 1 of 2
Pro Tip 1/3
Approximate Quantity
Use 'several' when the exact number is unknown or unnecessary to specify. I've read several books by that author.
Pro Tip 2/3
Quantity Impact
'Several' implies enough quantity to be noteworthy but not overwhelming. Several students volunteered for the project.
Pro Tip 3/3
Not Precise
Avoid 'several' when precision is required; it is not specific. Several hours could mean three or maybe eight.