show up

To appear, arrive, or attend, especially suddenly or erratically.

To make visible or expose faults and deficiencies in, usually by outdoing, outperforming, or outcompeting another.

To be easily visible; to be conspicuous.

To make visible; to expose.

(old-fashioned) To produce an impression on observers; to come off.

The showing of a suspect to a victim by police in the hope of identifying the suspect as the culprit.

At Eton College, a reward for good schoolwork (which is shown to one's housemaster and tutor and signed).