From Longman Dictionary of Contemporary Englishpillarpil‧lar /ˈpɪlə $ -ər/ ●●○ noun [countable] 1 
a) TBBa tall upright round post used as a support for a roof or bridge Eight massive stone pillars supported the roof. b) TBa tall upright round post, usually made of stone, put up to remind people of an important person or event2 → pillar of society/the community/the church etc3 BASICa very important part of a system of beliefs or ideaspillar of One of the pillars of a civilized society must be that everyone has equal access to the legal system.4 → be driven/pushed from pillar to post5 → be a pillar of strength6 → pillar of dust/smoke/flame etc
a) TBBa tall upright round post used as a support for a roof or bridge Eight massive stone pillars supported the roof. b) TBa tall upright round post, usually made of stone, put up to remind people of an important person or event2 → pillar of society/the community/the church etc3 BASICa very important part of a system of beliefs or ideaspillar of One of the pillars of a civilized society must be that everyone has equal access to the legal system.4 → be driven/pushed from pillar to post5 → be a pillar of strength6 → pillar of dust/smoke/flame etcExamples from the Corpus
pillar• Never mind that he had been a pillar of the regime and was approved on to the ballot by the Council of Guardians.• I run between the concrete pillars holding up the elevated railway, on to the steep stairs.• This takes us right back to the first pillar of meaningful work: freedom.• Below, dim curds of refuse lay clotted about the glass pillars of the Maserati Mall.• The dome was entire gold, standing upon three hundred pillars of precious stones.• Athelstan gazed at the square, squat pillars decorated with greenery like his own in Southwark, though not as beautiful.• IBM's three pillars of business wisdom are service, people, and perfection.• A white pillar of steam marked its finale.• Outside the stately music hall, two-story white pillars are quietly rotting away.Origin pillar (1200-1300) Old French piler, from Latin pila 