English Reference
adjective · noun

optimum

adj. · n.
US /ˈɑptəməm/ UK /ˈɒptɪməm/ op·ti·mum UK spelling optimums

  1. 01 B2 Upper Intermediate Academic

    adj.the best or most suitable for a particular purpose.

    adj.denoting the most advantageous or favourable condition for a specific result. Usually non-gradable.

    Simple

    The plants need the optimum amount of sunlight to grow quickly.

    In context

    The engineering team identified the optimum temperature for the chemical reaction to ensure maximum yield without damaging the equipment.

    Usage

    Often used before a noun to describe conditions, levels, or timing.

  2. 02 C1 Advanced AcademicTechnical

    n.the best possible level or state for something.

    n.the most favourable condition or greatest degree possible under specific circumstances.

    Simple

    The athlete reached his physical optimum just before the competition started.

    In context

    The experiment sought to determine the biological optimum for the species' growth within a controlled laboratory environment.

    Usage

    Usually used with 'the' or a possessive pronoun.

  3. 03 C2 Proficiency TechnicalAcademic Science

    n.a long period of time in history when the weather was consistently warm.

    n.a geological or historical period characterized by a persistently warm climate.

    Simple

    During the medieval optimum, many crops grew in places that are now too cold.

    In context

    The Holocene climate optimum allowed for significant shifts in vegetation patterns across the northern hemisphere due to sustained higher temperatures.

    climatic optimum

It was wonderful." In qualifying, Gasly was positioned second last in the train of cars on the final qualifying run, the absolute optimum place in terms of a slipstream.

BBC News· 5 Sept 2026

From New Latin, neuter of Latin optimus (“best, very good”), from the root in ops (“work”) or omnis (“all”).

Etymology adapted from Wiktionary, available under CC BY-SA 4.0.

This entry
Origin Latin optimus
Level C1 · Advanced
Frequency Frequent
Updated