What is a spaghetti measurer used for?

You're likely thinking of a spaghetti server, not a "spaghetti measurer".

A spaghetti server is a kitchen utensil specifically designed for serving spaghetti. It has two long, curved prongs that can easily scoop up spaghetti strands and transfer them to plates. It's much more efficient and less messy than using a fork or spoon.

There's no such thing as a "spaghetti measurer". You wouldn't typically need to measure spaghetti in the same way you would other ingredients.