[(как etc +) NP; subj-compl with быть (subj: human or concr) or adv (var. with как etc only); fixed WO]
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⇒ (a person or thing is) a source of constant irritation to s.o. by his or its presence:
- X (y Y-a) как бельмо на глазу{{}}≈ X is a thorn in Y's side (flesh);
- X is a thorn (a burr) in the side of Y;
- [in limited contexts] X sticks out like a sore thumb;
- thing X is an eyesore;
- thing X is a blot on the landscape.
♦ Опора своему брату и заступник всех обиженных... он [Браджеш] был, конечно, бельмом на глазу у раджи (Аллилуева 2). То his brother he [Brajesh] had been a real support, a protector to the wronged. ... As a result, he became a thorn in the side of the Raja (2a).
Большой русско-английский фразеологический словарь. — М.: ACT-ПРЕСС КНИГА. С.И. Лубенская. 2004.