I suppose because it sounds similar to words ending in 'er'.
New words, one handy idiom, and a 2-minute quiz — delivered to your inbox to keep your streak alive.
Nona The BritI suppose because it sounds similar to words ending in 'er'.And the correct spelling can easily by learned by thinking of "grammatical".
AnonymousI'm American and we do actually use more words that end with 'er' more than 'ar'.That's true for all varieties of English. There is nothing special about American English in this respect.