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Showing results for complex. Search instead for complexa.
Definitions

complex

[kuhm-pleks, kom-pleks, kom-pleks] / kəmˈplɛks, ˈkɒm plɛks, ˈkɒm plɛks /
ADJECTIVE
involved, intricate
Synonyms
STRONGEST
complicated convoluted
STRONG
composite compound conglomerate manifold mosaic motley multiple multiplex
WEAK
circuitous compounded confused elaborate entangled heterogeneous knotty labyrinthine mingled miscellaneous mixed mixed-up multifarious multiform tangled tortuous variegated
Antonyms
STRONGEST
simple
STRONG
single uniform unmixed
WEAK
apparent clear direct discernible easy evident homogeneous obvious plain
ADJECTIVE
difficult to understand
Synonyms
STRONGEST
complicated convoluted disturbing intricate obscure perplexing sophisticated
STRONG
byzantine winding
WEAK
Daedalean Gordian abstruse bewildering circuitous confused crabbed cryptic discursive disordered enigmatic entangled excursive hidden impenetrable inscrutable interwoven involved jumbled knotted knotty labyrinthine mazy meandering mingled mixed muddled paradoxical puzzling rambling recondite round-about sinuous snarled tangled tortuous undecipherable unfathomable
Antonyms
STRONGEST
easy simple
WEAK
apparent clear direct discernible evident homogeneous obvious plain uniform
NOUN
composite, aggregate
Synonyms
STRONGEST
compound network structure system
STRONG
association conglomerate ecosystem entanglement group organization scheme syndrome synthesis totality
Antonyms
STRONG
division separation
NOUN
psychological problem
Synonyms
STRONG
anxiety fear fixation hang-up insanity mania neurosis obsession phobia preoccupation repression
WEAK
a thing about something exaggerated reaction fixed idea idée fixe
Antonyms
STRONG
balance sanity

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.

The complex mission quickly ran into problems, officials said.

From The Wall Street Journal • Apr. 5, 2026

Officials say the final rescue required a complex operation involving special forces, aircraft, and intelligence support, carried out amid active threats.

From Salon • Apr. 5, 2026

As research continues, Mars is proving to be far more complex than once thought, with many of its secrets still waiting to be uncovered.

From Science Daily • Apr. 5, 2026

In the first 24 hours of Operation Epic Fury, US forces struck over 1,000 targets, including a school housed in a building previously used as a military complex, according to various media reports.

From Barron's • Apr. 5, 2026

They vanished into a complex the size of a small city.

From "The Mona Lisa Vanishes" by Nicholas Day

From Roget's 21st Century Thesaurus, Third Edition Copyright © 2013 by the Philip Lief Group.