doser
/ˈdoʊsər/Definitions
1. noun
A device used to dispense a measured amount of a substance, especially a liquid, at regular intervals.
“The gardener used a doser to fertilize the plants evenly.”
2. noun
A person who supplies or provides something, especially a controlled amount, over a period of time.
“The doser of the medication was responsible for administering it to the patients.”