IPA: /ˌdɪs.kənˈtɛnt.mənt/
KK: /dɪsˈkɒntɛntmənt/
A feeling of unhappiness or dissatisfaction with one's situation or circumstances.
Her discontentment with the job led her to seek new opportunities.
Discontentment is formed from "dis-" (meaning apart or away) and "content" (from Latin "contentus", meaning satisfied or pleased) and "-ment" (a suffix used to form nouns indicating an action or resulting state). The word describes a state of being away from satisfaction or a feeling of unhappiness.
Think of being 'away' ('dis-') from feeling 'satisfied' ('content') — that's why discontentment means a lack of satisfaction.