Document Type


Publication Date



We characterise quasivarieties and varieties of ordered algebras categorically in terms of regularity, exactness and the existence of a suitable generator. The notions of regularity and exactness need to be understood in the sense of category theory enriched over posets.

We also prove that finitary varieties of ordered algebras are cocompletions of their theories under sifted colimits (again, in the enriched sense).


This is a pre-copy-editing, author-produced PDF of an article accepted for publication in Mathematical Structures in Computer Science, volume27, number 7, in 2017 following peer review. The definitive publisher-authenticated version is available online at DOI: 10.1017/S096012951500050X.


Cambridge University Press



To view the content in your browser, please download Adobe Reader or, alternately,
you may Download the file to your hard drive.

NOTE: The latest versions of Adobe Reader do not support viewing PDF files within Firefox on Mac OS and if you are using a modern (Intel) Mac, there is no official plugin for viewing PDF files within the browser window.