Copyright term
The duration of copyright protection before a work enters the public domain. In most countries, compositions are protected for the life of the author plus 70 years. Sound recordings may have different (often shorter or jurisdictionally variable) terms.
Articles about Copyright term

LOMO: What to Know Before Signing with Songtrust
LOMO agreements transfer publishing rights for the entire life of copyright, not a fixed term. Before signing with Songtrust or any publisher offering LOMO terms, songwriters need to understand exactly what rights they're assigning, whether reversion is possible, and how these deals compare to standard publishing contracts.

Publishing Glossary Music Terms: Every Term Independent Artists Need to Know
Music publishing terminology is deliberately opaque, designed by an industry that profits from confusion. This glossary translates the language of royalties, rights, and revenue streams into plain terms independent artists can use to get paid correctly.