The definition of wistful refers to being full of melancholy or yearning, or having a mournful or regretful longing.(adjective)
An example of wistful is when you look back on your past and wish you had done something differently.
See wistful in Webster's New World College Dictionary
Origin: altered (modeled on wishful) < earlier wistly, attentive
See wistful in American Heritage Dictionary 4
Origin: From obsolete wistly, intently.
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