side effect

noun

any effect of a drug, chemical, or other medicine that is in addition to its intended effect, especially an effect that is harmful or unpleasant.

any accompanying or consequential and usually detrimental effect:

the side effects of air pollution.

Also, side-effect.

Origin

1880-85

Examples from the web for side effect

Furthermore, the satellite measurements have helped flag a worrying side effect of excessive groundwater extraction.
Germ theory, which secularized infectious disease, had a side effect: it sacralized epidemiology.
In fact, such image correction is merely a side effect of what is genuinely different about the technology.
The side effect is that whatever is on the oven floor cooks extremely quickly.
These creatures had not died as a side effect of agriculture.
Ala, one little side effect could be that all the bio living things could become its food source for its perpetuation.
The side effect is that if the original poster keeps posting that the bot will also keep posting.
One unfortunate side effect of this system is that if you find a new weapon while adventuring, you have no choice but to equip it.
The side effect of the process is that the coil expands and explodes violently inside the chamber.
Curbing the excesses of wealth, then, will be a side effect of regulations designed to make capitalism work better.

British Dictionary definitions for side effect

noun

any unwanted nontherapeutic effect caused by a drug Compare aftereffect (sense 2)

any secondary effect, esp an undesirable one

Word Origin and History for side effect

also side-effect, 1884, from side (adj.) + effect (n.). Medical use, with reference to drugs, is recorded from 1939.

side effect in Medicine

side effect n.
A peripheral or secondary effect, especially an undesirable secondary effect of a drug or therapeutic regimen.