Working cattle dogs that drive stock by nipping at heels

• Especially Australian Cattle Dogs; also any dog that heels well

Subservient political hangers-on or operatives attached to a boss

Team ropers who lasso a steer's hind feet after the header turns it

People who run very fast; swift runners

Gamecocks that strike effectively with their heels or spurs

Yale students undertaking tryouts for student publications; trainee student journalists