If you're referring to a scientific tool, the most likely answer is a dropper. Droppers are small, glass or plastic tubes with a bulb on one end and a narrow tip on the other. They are used to precisely dispense small quantities of liquid, often just a few drops at a time.
Here are some other possibilities:
* Micropipette: This is a laboratory tool designed to precisely measure and dispense very small volumes of liquids, usually in the microliter range (one microliter is one-millionth of a liter).
* Capillary tube: These are thin, glass tubes that draw liquids upwards due to capillary action. They are often used in chemistry to measure the surface tension of liquids.
* Microcentrifuge tube: These small, plastic tubes are used to hold and centrifuge small volumes of liquids. They are often used in molecular biology and other fields.
If you're thinking of a specific scientific context, please provide more information so I can give you a more precise answer.
