I'm discombublated why none of my contract law textbooks define 'covenant' when they use it many times, including Anson's Law of Contract (2016 30 ed) and Contract Law: Text, Cases, and Materials (2018 8 ed).
Google furnished some articles defining 'covenant', but in US law by
- Eric Lambert BA in Economics, Math, Business, University of Rochester. JD Cornell.
Raymond Millien BS in Computer Science from Columbia University (New York), and a JD from The George Washington University Law School (Washington D.C.)
- Upcounsel.com, but I distrust this as the author(s) is undeclared.
Thomson Reuters Practical Law's glossary is too snippety.