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 risk of complications from not receiving a vitamin K shot at birth far outweighs the risks of the injection itself. —Dr. Jade Cobern, ABC News, 23 Jan. 2026

Other groups that are more likely to suffer from measles complications include adults older than 20 years old, pregnant women and people with weakened immune systems, the federal health agency said. —Hali Smith, Idaho Statesman, 22 Jan. 2026

Given the complication — and the fact that the woman’s testimony underpins the case — prosecutors want the court to compel her to appear for Tran’s trial in early March. —Jakob Rodgers, Mercury News, 22 Jan. 2026

Although Boyd was later released, he was readmitted during the Thanksgiving holiday after suffering health complications related to the shooting and remains hospitalized. —Preezy Brown, VIBE.com, 22 Jan. 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