Something produced each hour.
"The factory produces an hourly batch of widgets to ensure steady output throughout the day."
In plain English: An hourly is someone who gets paid based on how many hours they work instead of getting a fixed amount for each job or project.
"The delivery charge is fifty dollars hourly, so you can expect to pay more if the job takes longer than planned."
Occurring every hour.
"The train runs hourly, arriving at the station on the top of every hour."
At intervals of an hour.
"The gardener watered the plants hourly throughout the day to keep them hydrated."
The word hourly is formed by adding the suffix -ly to the noun hour. It entered English as a straightforward combination meaning "occurring every hour."