Measurements without a dimension (raw number)

I'm translating some documents to English which deal with some measurements. Most of the measurements have a unit dimension (length is in meters, weight is in kilograms, etc) but some of them do not have a specific dimension, e.g. Number of samples.

What word to use to describe such measurements? The direct translation of the original terms leaves me with "undimensional", but I don't think that's it.

Solution 1:

Actually number of samples does have a unit, i.e. samples. So you could say:

I have 101 samples

Just as you can say

I ran 100 km.

So if you are counting something, e.g. samples, apples, people, etc., then use that as the unit.

A quantity without a unit is often a ratio, e.g. a ratio of length (metres) to width (metres) would have no units because metre/metre cancels out; although ratio is probably too broad a term, since it doesn't exclude units.

If you want to represent a number that has no dimension then dimensionless is an accepted term.

Other possible terms:

• % (percent)
• ppm (parts per million)
• degrees

More are listed in the above linked Wikipedia article.

These all depend on what you are measuring.