Remember the criterion?

Criterion Hotel, Oamaru                                               Image: Manatu Taonga

Some useful words seem to just fall out of favour, like gist and bunkum and visage. One that’s gone missing is criterion. It’s the singular of criteria. It means a principle, a standard, a reference point, a basis for comparison. 

There are some fine old Criterion hotels in Australia and New Zealand, but the word in its original sense rarely gets an outing these days. The trend is to use criteria, whether you mean the singular or the plural:

✖ Excellence in design was the main criteria for the award.

If are only referring to one, use criterion:
          ✔ Excellence in design was the main criterion for the award.

If there are more than one, use criteria, but not with a singular verb:

✖ The criteria for the welfare schemes varies across the country.  

The plural takes a plural verb:

✔ The criteria for the welfare schemes vary across the country.