trot: [13] Trot’s closest English relative is probably tread. It was borrowed from Old French troter, which went back via Vulgar Latin *trottāre to a Frankish *trottōn. This seems to have been derived from the same Germanic base as produced English tread. The colloquial use of the noun for ‘diarrhoea’ dates from the early 19th century – originally in the singular, but since at least the early 20th century in the plural, the trots. => tread
