A teaspoon is a small spoon used for measuring and serving food. It is typically used to measure out small amounts of ingredients, such as spices, when cooking or baking. It is also used to serve small portions of food, such as soup or ice cream. The term 'teaspoon' is derived from the Old English word 'tēospōn', which means 'a teaspoonful'. The answer to the crossword puzzle is 'DOSE', which is an abbreviation of the word 'DOSAGE'.