also: オプチミスト
noun
A person who tends to see the positive side of things. Loanword from English; used in both casual and formal contexts.
彼はどんな状況でも前向きなオプティミストだ。
He is an optimist who stays positive in any situation.
オプティミストとペシミストでは、同じ出来事
Optimists and pessimists interpret the same event differently.