Dearest Molly: “-or” or “-er”. No, I am not clearing my throat. Not to mention “-or/-our”. Don’t let’s go there today. The choice between the “-or” and “-er” endings is one of the hurdles in our Spelling Bee.

Let us try to work out a rule (realising that spelling rules are made to be broken). “-Or” is the Latin agent-noun ending: perpetrator. It corresponds to the “-er” agent-noun ending for English verbs: doer. English verbs derived from the supine (no, not lying face upwards: a noun made from a verb) stem usually prefer the Latin “-or” ending to the English “-er”. But there are many others, such as act, credit, invent, possess, prosecute, protect. Some other verbs, not corresponding to the above description (ie, not derived from Latin) make agent-nouns in “-or” owing to their passage through French, or through some other circumstance: conqueror, governor, porveyor. It is corrupter, but corrector; deserter, but abductor; dispenser, but distributor; eraser but ejector.

Some verbs generate both “-er” and “-or” endings. They generally prefer “-er” for the personal, and “-or” for the mechanical agent. I am an adapter looking for an adaptor. Will my car distributer please find me a distributor? A conveyer needs a conveyor belt. Or they keep the “-or” ending for lawyers, and let us hoi polloi settle for “-er”. Abettor for lawyers; abetter for us. Vendor for the wigs: vender for us pigtails.

So let us try to draw up some rules. If you have a non-Latin verb or noun, go for “-er”: hunter, farmer. Go for “-er” for a “localising suffix” (area and place-names, dear): New Yorker, Highlander. “-Er” as a comparative suffix for many adjectives: older. As a colloquial replacement for a final syllable: feller (not lumberjacks, but “Who’s your feller?”) And as a variant for of “-re”, as in center for centre. Americans only, please. For Latinate verbs, go for “-or”: educator. Also “-or” as an ending on borrowed agent words: eg, doctor, ambassador. And as a variant for of “-our” (where we are not going today): colour/color. The point at which “-er” and “-or” overlap most significantly is in forming agent words out of English verbs. Even good spellers sometimes stumble over these hurdles. These are deep waters, Molly. But with your young memory you can implant them in your mind for our Spelling Bee; and for life.

For the latest information on The Times Spelling Bee visit timesonline.co.uk/spellingbee

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