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副作用 (fukusayou) Japanese meaning: side effect | Kotomora

副ふく作さ用よう

ふ

く

さ

よ

う

Common word›JLPTN2›Freq.FrequencyTop 10,000

Meanings

1

side effect; adverse reaction

Primarily a medical term for unintended effects of a drug or treatment, but also used broadly for any secondary, often negative, consequence.

この薬くすりの副ふく作さ用ようと

し

て

眠ねむ

気け

が

出で

る

こと

が

あり

ます

。

Drowsiness may occur as a side effect of this medicine.

新あたらしい政せい策さくの副ふく作さ用ようで、中ちゅう小しょう企き業ぎょうの負ふ担たんが増ふえた。

As a side effect of the new policy, the burden on small and medium-sized enterprises increased.

Usage patterns

〈物もの〉に副ふく作さ用ようがあるfor something (a drug, treatment) to have side effects
この薬くすりには眠ねむくなる副ふく作さ用ようがある。
This medicine has the side effect of making you drowsy.
副ふく作さ用ようが出でるfor a side effect to appear/occur
服ふく用ようしてから副ふく作さ用ようが出でた。
A side effect appeared after taking the medicine.
副ふく作さ用ようを起おこすto cause a side effect
その治ち療りょうは重おもい副ふく作さ用ようを起おこすことがある。
That treatment can sometimes cause serious side effects.
副作用ふくさようの心配しんぱいがあるto have concerns about a possible side effect
新あたらしい薬くすりには副ふく作さ用ようの心しん配ぱいがある。
There are concerns about side effects with the new medicine.

Kanji

副vice-, assistant, aide
作make, production, prepare
用utilize, business, service

Related words

副ふく反はん応のう
副反応 is typically used for vaccine-related adverse reactions, while 副作用 is the general term for side effects of any drug or treatment.
後こう遺い症しょう
副作用 refers to unwanted side effects that occur during or from a treatment/drug, while 後遺症 refers to symptoms that linger after the original illness or injury has otherwise resolved.
薬やく害がい
副作用 is the neutral term for any side effect of a drug, while 薬害 specifically refers to serious harm caused by a drug, often framed as a social or legal issue.
弊へい害がいN1
副作用 literally means a side effect (esp. of medicine) but is often used figuratively like 弊害 for unintended negative consequences.

Don't confuse with

作さ用ようN2
作用 simply means an effect or action in a neutral sense, whereas 副作用 specifically refers to an unintended, secondary (often negative) effect.
逆ぎゃく効こう果かN1
副作用 refers to a side effect, often medical, that accompanies a main effect, whereas 逆効果 means the action itself produced the opposite of what was intended.
副ふく産さん物ぶつ
副作用 refers specifically to a negative side effect, especially of medicine, whereas 副産物 can be neutral or even beneficial.

Built from

副ふく+作さ用よう

Etymology

Compound of 副 (ふく, 'secondary, auxiliary') and 作用 (さよう, 'action, effect'). The term is a direct translation of the English 'side effect' and entered Japanese through medical terminology.