composed of many interconnected parts; compound; composite

a complex highway system.

characterized by a very complicated or involved arrangement of parts, units, etc.

complex machinery.

so complicated or intricate as to be hard to understand or deal with

a complex problem.

Grammar .

(of a word) consisting of two parts, at least one of which is a bound form, as childish, which consists of the word child and the bound form -ish.

complex sentence.

Mathematics . pertaining to or using complex numbers

complex methods; complex vector space.

an intricate or complicated association or assemblage of related things, parts, units, etc.

the entire complex of our educational system; an apartment complex.

Psychology . a system of interrelated, emotion-charged ideas, feelings, memories, and impulses that is usually repressed and that gives rise to abnormal or pathological behavior.

a fixed idea; an obsessive notion.

Mathematics .

an arbitrary set of elements of a group.

a collection of simplexes having specified properties.

Also called coordination compound. Chemistry . a compound in which independently existing molecules or ions of a nonmetal (complexing agent) form coordinate bonds with a metal atom or ion. Compare ligand ( def. 2 ) .

Biochemistry . an entity composed of molecules in which the constituents maintain much of their chemical identity

receptor-hormone complex, enzyme-substrate complex.

Chemistry . to form a complex with.

Chemistry . to form a complex.

adjective

clear , easy , evident , homogeneous , obvious , plain , simple , uniform , apparent , direct , discernible , incomplex

adjective

circuitous , complicated , composite , compound , compounded , confused , conglomerate , convoluted , elaborate , entangled , heterogeneous , knotty , labyrinthine , manifold , mingled , miscellaneous , mixed , mixed-up , mosaic , motley , multifarious , multiform , multiple , multiplex , tangled , tortuous , variegatednotes:something complex may be well-organized and logically constructed as well as subtle and intricate , while a thing that is complicated will have something irregular , perverse , asymmetrical in addition to fundamental intricacy; complex is more formal and technical (a problem in mathematics is complex) while something like personal life can be complicated , abstruse , bewildering , byzantine , crabbed , cryptic , daedalean , discursive , disordered , disturbing , enigmatic , excursive , gordian , hidden , impenetrable , inscrutable , interwoven , intricate , involved , jumbled , knotted , mazy , meandering , muddled , obscure , paradoxical , perplexing , puzzling , rambling , recondite , round-about , sinuous , snarled , sophisticated , undecipherable , unfathomable , windingnotes:something complex may be well-organized and logically constructed as well as subtle and intricate , daedal , daedalian , involute , abstract , daedalic , devious , involuted , labyrinthian , reticular

noun

association , compound , conglomerate , ecosystem , entanglement , group , network , organization , scheme , structure , syndrome , synthesis , system , totalitynotes:something complex may be well-organized and logically constructed as well as subtle and intricate , while a thing that is complicated will have something irregular , perverse , asymmetrical in addition to fundamental intricacy; complex is more formal and technical (a problem in mathematics is complex) while something like personal life can be complicated , anxiety , a thing about something , exaggerated reaction , fear , fixation , fixed idea , hang-up * , ide fixe , insanity , mania , neurosis , obsession , phobia , preoccupation , repressionnotes:something complex may be well-organized and logically constructed as well as subtle and intricate , headquarters , station , hang-up* , complexity , complicacy , complicated , composite , compositeness , convoluted , cryptic , difficult , entangled , hard , intricacy , intricate , involved , involvement , knotty , labyrinth , labyrinthine , maelstrom , manifold , maze , mixed , perplexed , puzzling , sinuosity , sophisticated , tangled