Synonyms

suboptimal

American

[suhb-op-tuh-muhl] / sʌbˈɒp tə məl /

Also suboptimum

adjective

being below an optimal level or standard.

Usage

What does suboptimal mean? Suboptimal means below the optimal (best possible) level or standard. The words optimal and optimum both describe an ideal or perfect level, degree, result, or similar thing. Suboptimal means something has fallen short of that level. It is often used in phrases like suboptimal performance and suboptimal conditions. Example: The patient’s heart is performing at a suboptimal level.

Etymology

Origin of suboptimal

First recorded in 1930–35; sub- + optimal

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Appeared in the December 24, 2025, print edition as 'A Perfect Christmas Is Suboptimal'.

From The Wall Street Journal • Dec. 23, 2025

Suboptimal nutrition during this stage also may interfere with optimal growth and development.

From Salon • Jan. 19, 2023

Suboptimal cost profile: The project costs too much.

From Time Magazine Archive

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023