pessimistic

What it means

1. Marked by pessimism and little hopefulness; expecting the worst.

   a pessimistic view of the future

   1 more example

   Some, noting the obvious analogies between Soviet Communism and Nazism, had pessimistic forebodings as to the inevitability of totalitarian systems throughout the world.

   1978 [1976], Leszek Kołakowski, translated by P[aul] S[teven] Falla, Main Currents of Marxism, volume III: The Breakdown, Oxford: Clarendon Press, translation of Główne nurty marksizmu: rozkład (in Polish), →ISBN, →OCLC, page 215

2. Pertaining to the worst-case scenario.

   a pessimistic estimate

   1 more example

   However pessimistic their predictions, most scientists and scholars who warn of impending disaster are really acting from antidystopian motives.

   1996, George Thomas Kurian, Graham Thomas Tate Molitor, Encyclopedia of the future, volume 1, page 212

3. computingTaking out exclusive locks on data to prevent conflicts with other processes that might modify it.

   pessimistic concurrency; pessimistic locking

In a sentence

a pessimistic view of the future

Where it comes from

From pessimist + -ic.