| OST | German chemist (1853-1932) |
|---|---|
| OST | (chemistry) the theory that all indicators are either weak acids or weak bases in which the color of the ionized form is different from the color before dissociation |
| OST | a Ugric language (related to Hungarian) spoken by the Ostyak people |
| OST | a member of the nomadic Ugrian people living in northwestern Siberia (east of the Ural mountains) |
| OST | the Uralic language spoken by the Ostyak-Samoyed people |
| OST | one of the people of mixed Ostyak and Samoyed origin in Siberia |