complication

noun

com·​pli·​ca·​tion ˌkäm-plə-ˈkā-shən 

1

a

: complexity, intricacy

especially : a situation or a detail of character complicating the main thread of a plot

b

: a making difficult, involved, or intricate

c

: a complex or intricate feature or element

d

: a difficult factor or issue often appearing unexpectedly and changing existing plans, methods, or attitudes

2

: a secondary disease or condition developing in the course of a primary disease or condition

Synonyms of complication

• difficulty
• complexity

Examples of complication in a Sentence

The negotiations stalled when complications arose.

Pneumonia is a common complication of AIDS.

She experienced complications during her pregnancy.

The patient died of complications from surgery.

Recent Examples on the Web

The person who died suffered from neurological complications of the disease, which affect about one in 150 people infected, according to a county news release. — Daniel Lempres, Sacbee.com, 9 Sep. 2026

The doctor said his colleagues are struggling to treat infected children who often arrive at the hospital with serious complications like pneumonia, diarrhea and encephalitis, or brain swelling. — Julhas Alam, Los Angeles Times, 9 Sep. 2026

Users will be able to view their heart rate in real time with a new heart rate watch face special feature (also known as a complication). — ArsTechnica, 9 Sep. 2026

But Kelsi Kiper and others fear that any complications in enforcing the new ballot requirements for other types of ballots could have knock-on effects. — Hansi Lo Wang, NPR, 9 Sep. 2026

Word History

Etymology

Middle English complicacioun, borrowed from Late Latin complicātiōn-, complicātiō "folding together, conglomeration," from Latin complicāre "to fold together, fold up" + -tiōn-, -tiō, suffix of verbal action — more at complicate entry 2

First Known Use

15th century, in the meaning defined at sense 1a

Rhymes for complication

• abdication
• aberration
• abjuration
• abnegation
• abrogation
• acceptation
• acclamation
• acclimation
• accusation
• activation
• actuation
• acylation

Kids Definition

complication

noun

com·​pli·​ca·​tion ˌkäm-plə-ˈkā-shən 

1

a

: an act or instance of complicating something

b

: a situation or detail of character that complicates a plot

c

: a complex feature or element

d

: something that makes a situation more complicated or difficult

we were unable to agree when complications arose

2

: a disease or bodily condition existing at the same time as and affecting the course or severity of another disease or condition

Medical Definition

complication

noun

com·​pli·​ca·​tion ˌkäm-plə-ˈkā-shən 

: a secondary disease or condition that develops in the course of a primary disease or condition and arises either as a result of it or from independent causes