A Fly in the Ointment
Meaning
A small but irritating flaw that spoils the whole thing.
Example
She has scored low marks in GMAT. But that can be treated as A Fly in the Ointment.
Origin
These days ointments are chiefly for medicinal use – just the thing for rubbing on that nasty rash. In earlier times though ointments were more likely to be creams or oils with a cosmetic or ceremonial use. Literally, ointment was the substance one was anointed with. There is considerable anointing in Bible stories and it isn’t surprising therefore that this phrase has a biblical origin. Ecclesiastes 10:1 (King James Version) has:
“Dead flies cause the ointment of the apothecary to send forth a stinking savour: so doth a little folly him that is in reputation for wisdom and honour.”
Our contemporary phrase ‘the fly in the ointment’ didn’t appear until later. The earliest example that I have found in print of that precise text is in John Norris’ A Practical Treatise Concerning Humility, 1707:
‘Tis that dead fly in the ointment of the Apothecary.