trot: a gait faster than a walk; diagonally opposite legs strike the ground together
entity: that which is perceived or known or inferred to have its own distinct existence (living or nonliving)
metoprolol: beta blocker (trade name Lopressor) used in treating hypertension and angina and arrhythmia and acute myocardial infarction; has adverse side effects (depression and exacerbation of congestive heart failure etc.)