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 trial date could still be delayed by disputes over classified evidence and other complications arising from the extraordinary case. — Kaelan Deese, The Washington Examiner, 22 July 2026

What happens if complications arise after treatment in Mexico (or another country)? — Deidre Popovich, The Conversation, 22 July 2026

West Nile virus can cause severe complications in the form of neuroinvasive disease. — Eva Flowe july 21, Charlotte Observer, 21 July 2026

Inhaling these particles triggers inflammation, increasing risks of cardiovascular complications and stroke, particularly for vulnerable populations like children, older adults, and those with chronic conditions. — Jamie Gold, Forbes.com, 21 July 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