Definition: A sassy and genius mix between pesimistic and realistic describing a feeling normally associated with doucebag boys who refuse to act their age.
Use in a sentence: Sally, don't be so fessimistic, I'm sure Hector will call you tonight.
Explanation: If Sally is true to her fessimistic feelings, she won't be let down when Hector doesn't call.. because she didn't expect him to. What a jerkface.
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