Exasperate (verb)

1. Irritate or annoy (someone) greatly.
2. Make (a situation or problem) more difficult or intense.

Origin:

Mid 16th century: from latin exasperare, from ex- "thoroughly" + asper "rough, harsh".

Examples:

1. His constant complaining exasperated her.
2. She was exasperated by his lack of understanding.
3. The delay in the flight's arrival was exasperating.
4. The situation was already bad, but his interference only served to exasperate it.
5. The child's constant questioning was beginning to exasperate the teacher.