Sentence:  Cerebellar dysfunction is characterized by truncal ataxia, a broad-based stance, dysmetria in which the limbs either <WSD>overstep</WSD> (hypermetria) or understep (hypometria), and tremor that is most pronounced when the animal attempts a goal-orientated movement (intention tremor). 
Meaning of the word marked with <WSD> tags:  To take a step in which the foot touches ground too far forward.