side-effect
side-effect — noun
1. A negative physical reaction that a medicine, injection, or treatment causes bey
A negative physical reaction that a medicine, injection, or treatment causes beyond the desired healing effect.
Christopher stopped taking the painkillers because the side effects made him feel dizzy all day.
often plural: side effects
The clinic warned that a side effect of this injection is temporary skin redness.
Rania developed a skin rash as a side effect of the antibiotic cream.
Lan checked the hospital pamphlet to see which side effects the chemotherapy might bring.
- adverse reaction
broader term covering any negative bodily response including allergies; more formal in register
- aftereffect
focuses on lingering effects that persist after treatment ends rather than concurrent effects
- complication
implies a more serious, often unexpected medical problem arising during a procedure
用法筆記
Frequently used in the plural form 'side effects' when listing or describing multiple reactions from a single course of treatment. Often paired with adjectives such as 'mild', 'serious', or 'rare'.
常見錯誤
2. An additional and often unintended consequence of an action, decision, or change
An additional and often unintended consequence of an action, decision, or change, beyond the originally intended outcome.
An unexpected side effect of the new road was that local shops gained more customers.
collocation: unexpected/welcome side effect of [situation]
Working from home had the welcome side effect of saving Asher money on transport.
The factory closure had side effects beyond the job losses the company planned for.
A welcome side effect of the rain was that the river refilled the park's lake.
- byproduct
more neutral in tone; does not imply whether the secondary result is good or bad
- consequence
broader and more general; can refer to the main result as well as secondary ones
- repercussion
often implies an indirect negative effect that spreads over time
用法筆記
Often modified by adjectives that describe the nature of the consequence, such as 'welcome', 'unexpected', 'unintended', or 'positive'. Unlike sense 1, this sense does not imply negativity.