optimistop‧ti‧mist /ˈɒptəmɪst $ ˈɑːp-/ noun [countable] 
He’s an eternal optimist (=he always believes that good things will happen).
EXAMPLES FROM OTHER DICTIONARIES
- Optimists still believe we can resolve the problem without going to war.
- You have to be an optimist to be in an occupation such as farming.
- But Stirling, the incurable optimist, was already making new plans.
- Diehard optimists, like Mr Pynzenyk, say that hyperinflation and economic collapse will eventually force the country to its senses.
- He had clean-cut, perfect features, an absolutely even gaze, and the erect, confident air of a nineteenth-century optimist.
- He is extremely serious, speaks slowly-almost grinding to a complete halt at times-and is not exactly the happy optimist.
- His trouble, Hicks thought, was that he was too much of an optimist, like all hustlers.
- Most entrepreneurs tend to be optimists.
- The perennial optimists would say that this is because of consumer demand.
Longman Language Activatorexpecting something good to happen
someone who is optimistic expects good things to happen: · In spite of all her problems she manages to remain optimistic.· an optimistic economic forecastoptimistic about: · I'm pretty optimistic about our chances of winning here today.optimistic that: · Are you still optimistic that the climbers can be rescued?cautiously/guardedly optimistic (=expecting good things to happen but knowing that they might not happen): · We are cautiously optimistic that the trade deal will go through.overly optimistic (=more optimistic than you should be): · The company was overly optimistic in its sale projections.
someone who always expects good things to happen: · Optimists still believe we can resolve the problem without going to war.
expressing a cheerful attitude and showing that you expect to succeed, even though the situation may not be encouraging: · The senator took an upbeat view of the Republicans' chances in the next election.upbeat about: · Analysts are more upbeat about the long-term outlook for the economy.
COLLOCATIONS FROM THE ENTRY He’s an eternal optimist (=he always believes that good things will happen).COLLOCATIONS FROM OTHER ENTRIES She’s an eternal optimist (=she always expects that good things will happen).
someone who believes that good things will happen OPP pessimist: He’s an eternal optimist (=he always believes that good things will happen). She’s an eternal optimist (=she always expects that good things will happen). He’s an eternal optimist (=he always believes that good things will happen).