[SAI_Peregrinus]

Tableware sets in the US commonly come with at least two different sizes of spoon. These usually bear no relation to the "measuring spoons" used to measure volume, though they are handy for stirring tea or eating soup (for the small & large spoons, respectively).

For people who cook in the US, a set of "measuring spoons" is a very common kitchen tool.

"Teaspoon" and "Tablespoon" are units of measurement of volume, not bits of silverware. "Tea spoon" and "Table spoon" or "Soup spoon" are pieces of silverware, not units of measure!

[beojan]

The one you stir tea with is also probably smaller than a teaspoon (probably about half a teaspoon).

[SAI_Peregrinus]

Yep, they're usually completely unrelated to the units of measure.