Definition of "peacocky"

From his short passes to the hip-length tan winter coat he slipped on after the game, Pennington proved in myriad ways that he was all about being practical, not peacocky.

2007 January 1, “With Wild-Card Spot Clinched, Jets Can Finally Talk Playoffs”, in New York Times‎

“Samson 4th” was third, a smart, peacocky horse, favoured by his marvellous action, which invariably catches the Judge's eye.

1882, Shire Horse Society, Shire Horse Stud Book, volume 3, page xix

The famous Biennial was won by Earl of Dartrey, a light, peacocky horse, who was, perhaps, better than he looked.

1891, Sir George Chetwynd, Racing Reminiscences and Experiences of the Turf, page 122