| arch | a genus of Elephantidae |
|---|---|
| arch | largest known mammoth |
| arch | of or associated with an archbishop |
| arch | any of various lecanoras that yield the dye archil |
| arch | a purplish dye obtained from orchil lichens |
| arch | a genus of Trochilidae |
| arch | a kind of hummingbird |
| arch | the superior of an abbey of monks |
| arch | Greek mathematician and physicist noted for his work in hydrostatics and mechanics and geometry (287-212 BC) |
| arch | (hydrostatics) the apparent loss in weight of a body immersed in a fluid is equal to the weight of the displaced fluid |
| arch | a Russian unit of length (71 cm) |
| arch | (architecture) forming or resembling an arch |