“Wikipedia
Pravni sistemi
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Elementi pravnog sistema su:
1. pravna ustanova ili pravni institut - skup pravnih normi koje se odnose na jedan isti društveni odnos ili njihovu grupu, a koje se zasnivaju na istim osnovnim načelima, tj. koje čine sastavni deo neke više celine.
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( http://sr.wikipedia.org/sr-el/Правни_системи )


BLACK’S LAW DICTIONARY
institution.
1. The commencement of something, such as a civil or criminal action.
2. An elementary rule, principle, or practice.
3. An established organization, esp. one of a public character, such as a facility for the treatment of mentally disabled persons.


OXFORD (OALD) DICTIONARY
institution
- 1 [countable] a large important organization that has a particular purpose, for example, a university or bank
(an educational/financial, etc. institution;
the Smithsonian Institution)
- 2 [countable] (usually disapproving) a building where people with special needs are taken care of, for example because they are old or mentally ill
(a mental institution;
We want this to be like a home, not an institution)
- 3 [countable] a custom or system that has existed for a long time among a particular group of people
(the institution of marriage)
- 4 [uncountable] the act of starting or introducing something such as a system or a law
(the institution of new safety procedures)
- 5 [countable] (informal, humorous) a person who is well known because they have been in a particular place or job for a long time
(You must know him - he's an institution around here!)
( http://oald8.oxfordlearnersdictionaries.com/dictionary/insti... )