Noun

(uncountable) Inadequacy or incompleteness.

* {{quote-book, year=1963, author=(Margery Allingham), title=(The China Governess)

, chapter=17 citation , passage=The face which emerged was not reassuring. […]. He was not a mongol but there was a deficiency of a sort there, and it was not made more pretty by a latter-day hair cut which involved eccentrically long elf-locks and oiled black curls.}}

(countable) An insufficiency, especially of something essential to health.

* {{quote-magazine, date=2013-08-31, volume=408, issue=8851, magazine=(The Economist)

, title= Promotion and self-promotion , passage=One of academia’s deficiencies is that, though its lecture halls and graduate schools are replete with women, its higher echelons are not. Often, this is seen as a phenomenon specific to the sciences. … In fact, the disparity applies to the whole grove. Another report from 2006, by the American Association of University Professors, found the same ratio in the faculties of arts, humanities and social science, too.}}

(geometry) The amount by which the number of double points on a curve is short of the maximum for curves of the same degree.

(geometry) The codimension of a linear system in the corresponding complete linear system.

Noun

(en noun)

A quirk, idiosyncrasy, or mannerism; unusual habit or way (usage is typically plural), that is slightly strange or silly.

Try to look past his foibles and see the friendly fellow underneath.

* 1915 ,

They made up for the respect with which unconsciously they treated him by laughing at his foibles and lamenting his vices.

* 1959 , Meriden Record, " An ounce of prevention", July 24 issue

Final fillip in the Vice-President's study has been a boning up]] on Premier Khrushchev's favorite foible , proverbs. The bibulous Russian leader likes to throw out homely [[homily, homilies in his speeches and conversations..

(fencing) Part of a sword between the middle and the point, weaker than the forte.

A weakness or failing of character.

* 1932 , , by William Floyd

Jesus is reverenced as the one man who has lived unspotted by the world, free from human foibles , able to redeem mankind by his example.