buggy
Word family
Synonym discussion
Sense: adjective/1
For adjective/1, buggy is the most natural everyday word for software, apps, games, or updates that contain errors and behave strangely. Glitchy is more informal and often suggests small but repeated problems, especially with screens, games, or streaming. Faulty is broader and can describe hardware, wiring, or any product with a defect, so it is less tied to computing. Unstable is common in technical writing when a system crashes, freezes, or changes state unexpectedly. Broken is the strongest simple word and often suggests that something does not work at all. A game can be buggy if some levels fail, but broken if it will not even start.
Etymology
The adjective buggy was formed in English from bug plus the ending -y and first meant 'full of bugs.' After bug also came to mean an error in a machine or computer program, buggy developed the computing sense as well. The noun buggy appeared in the 18th century for a light horse-drawn vehicle, but its exact origin is uncertain. Later, the noun was also used for a baby's wheeled chair and for small open motor vehicles.