EXAMPLES FROM THE WEB FOR OATS
The boy might find it if you put it among the oats—feedin' the horses, ye know.
Some had all the venison and bear meat they wanted, but no barley or oats.
I have seen barley and oats in that country three feet high.
The lad's hair was inclined to be carroty, while that of the girl suggested the color of oats.
Why, one might bury millions there without reaping a single bushel of oats!
Tim Brady should have got the top price for that oats of his, Pat.
Then he was put in a box stall and given three sheaves of oats.
Speed, done 'im in, savin' 'is country's 'time an' 'is country's oats; that done 'im in.
The Queen's feelin' her oats to-day, and I cal'late I can show him a few things.'
We did the oats and the corn and all the rest and, upon my word, I expected the hay.
Old English ate (plural atan) "grain of the oat plant, wild oats," of uncertain origin, possibly from Old Norse eitill "nodule," denoting a single grain, of unknown origin. The English word has cognates in Frisian and some Dutch dialects. Famously defined by Johnson as, "A grain, which in England is generally given to horses, but in Scotland supports the people."
The usual Germanic name is derived from Proto-Germanic *khabran (cf. Old Norse hafri, Dutch haver, source of haversack). Wild oats, "crop that one will regret sowing," is first attested 1560s, in reference to the folly of sowing these instead of good grain.
Hence, to feel (one's) oats "be lively," 1831, originally American English.