Proximate (adjective)

1. Closest in space or time; nearest or next.
2. Having a close causal relationship; directly responsible.

Origin:

Late 16th century: from latin proximatus 'approached', past participle of proximare, from proximus 'nearest'.

Examples:

1. The proximate cause of the accident was driver error.
2. The proximate cause of the fire was a faulty electrical connection.
3. The proximate cause of the headache was the stress of the long day.
4. The proximate reason for the break-up of the relationship was their incompatible goals.
5. The proximate cause of the increased traffic was the closure of the main road.