Teff or taf is an annual  grass, a species of lovegrass native to the northern Ethiopian Highlands of Northeast Africa. It has an attractive nutrition profile, being high in dietary fiber and iron  and providing protein and calcium.  Some people consider it to have a sour taste. It is similar to millet and quinoa  in cooking, but the seed  is much smaller, and thus cooks using less fuel.

Teff is an important food grain in Ethiopia and Eritrea, where it is used to make injera, and less so in India and Australia. (It is now raised in the USA, in Idaho in particular, with experimental plots in Kansas) Because of its small seeds (less than 1 mm diameter), one can hold enough to sow a large area in one hand. This property makes teff particularly suited to a seminomadic lifestyle.

Common names include teff, lovegrass, annual bunch grass (English); Ṭeff/Ṭéff (Amharic, both representing the same sound, an ejective consonant); Ṭaffi/xaffi (oromo, both representing the same sound); Ṭaff (Tigrinya); and mil éthiopien (French). It is also written as ttheff, tteff, thaff, tcheff, and thaft. The word "tef" is connected by folk etymology to the Ethio-Semitic root "ṭff", which means "lost" (because of the small size of the grain).

Teff is believed to have originated in Ethiopia between 4000 BC and 1000 BC. Genetic evidence points to E. pilosa as the most likely wild ancestor. A 19th century identification of teff seeds ...