THE GLOSSARY OF USEFUL WORDS 23: ‘SUPEREROGATORY’
The word superfluous is used all the time in speech and writing and can hardly be deemed superfluous. However, there is a synonym—namely, “supererogatory,”—which is hardly ever used but is actually very useful. Here is how it is defined in Webster’s Unabridged Dictionary Online:
1a:of, relating to, or characterized by supererogation
b:observed or performed to an extent not enjoined or required
2: that can be dispensed with:superfluous, nonessential

Next time I introduce myself as a substitute teacher to a class at Burr and Burton Academy as “Dr. S.,” I will be sure to add “as in supererogatory!”

MICHAEL SHAPIRO