Carbon sink 

A natural or artificial system that absorbs and stores more carbon dioxide (CO₂) than it releases, helping to reduce atmospheric CO₂ levels. Carbon sinks play a key role in mitigating climate change by removing and storing carbon over long periods.

Examples of natural carbon sinks include forests, soils, oceans and peatlands/wetlands. Technological (artificial) carbon sinks include geological storage, biochar and carbon capture and storage (CCS).