Ratting:

Ratting is a Dota 2 strategy that focuses on pushing side lanes, hitting buildings, and forcing the enemy team to respond instead of taking direct five-on-five fights.

It is usually done by a hero with high mobility, strong wave clear, or a safe escape, because the goal is to trade time and map pressure for objectives. Ratting matters because it can stretch the defending team across the map, buy space for teammates, and punish lineups that move slowly or group too early. A common example is a split-pushing hero clearing a lane, slipping past vision, and damaging a tier 2 tower while the enemy team is occupied elsewhere.

Related: Map Control