There are a lot of words in the English language that have a very similar meaning, but that are not always interchangeable. An example of this are the words dissatisfied and unsatisfied. To better understand when and how to use these words in a sentence, we will use an example.
Our sample sentence is: Kelly was unsatisfied with her husband’s explanation. The use of the word unsatisfied in this sentence implies that Kelly believed that something was missing from her husband’s explanation. There were some details that he left out or that he was omitting.
However, if we change the same sentence to: Kelly was dissatisfied with her husband’s explanation, it would imply that Kelly believed that her husband was lying to her. It could also imply that while the answer itself was complete, it was not the answer that Kelly was looking for.
Dissatisfaction gives the idea of a state of active displeasure. In the above-mentioned sentence, it could apply displeasure from the answer itself or from the incompleteness or wrongness of the answer.
Unsatisfied implies a lack of satisfaction, which in the above-mentioned example would stem from an answer that lacked important information or that did not answer the question completely.
The term dissatisfied can only be use to describe people. A person can go out to lunch and be dissatisfied with the amount of food they receive. However, you would never say that their hunger was dissatisfied. You could say that their hunger was unsatisfied.
Finally, the term unsatisfied implies that more of something is needed. Dissatisfied means that the quality of what was provided was poor.