To disappoint is defined as to let someone down or fail to fill his expectations for you.(verb)
When your parents hope you will become a doctor and you end up unemployed and sleeping on their sofa instead, this is an example of a situation where you disappoint your parents.
See disappoint in Webster's New World College Dictionary
Origin: ME disapointen < OFr desapointer: see dis- & appoint
See disappoint in American Heritage Dictionary 4
verb dis·ap·point·ed, dis·ap·point·ing, dis·ap·points verb, transitive
Origin: Middle English disappointen
Origin: , from Old French desapointier, to remove from office
Origin: : des-, dis-
Origin: + apointer, apointier, to appoint; see appoint.
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