The practice or method of fishing using gillnets.
From gillnet + -ing (gerund/present participle suffix). Formed in the 19th-20th centuries as gillnetting became an established commercial fishing practice.
Gillnetting became so dominant in the 20th century that it shaped entire fish populations—scientists can literally see which species survived by looking at what escaped the mesh size used in different regions.
Complete word intelligence in one call. Free tier — 50 lookups/day.