Dissatisfied applies only to people who are unhappy, frustrated or disappointed with a thing, person or situation. Examples:
- I was dissatisfied with the service I received at the restaurant.
- She was dissatisfied with his response to her question.
Unsatisfied refers to the feeling of needing more and can be used with abstract items. Examples:
- Despite the hearty meal, his hunger remained unsatisfied.
If you would like more example sentences please visit the British Corpus. Type your word in the search field and it will bring up examples of the word in use. A fantastic tool!
Credit where credit is due: I sourced this explanation from here http://www.dailywritingtips.com/dissatisfied-unsatisfied/
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