citric acid
A weak organic acid found in citrus fruits; used in food, cleaning, and biochemistry. Technical term in chemistry.
Lemons contain a lot of citric acid.
Citric acid is used as a food additive.
Standard modern spelling using katakana for the loanword portion and kanji for 酸.
Rarely used kanji form; the characters 枸櫞 are uncommon and may not be recognized by many readers.
From German 'Zitronensäure' (citric acid), adapted into Japanese as クエン酸, where クエン represents the 'citron' part and 酸 means 'acid'.