| osmiridium | (noun) a hard and corrosion resistant mineral that is a natural alloy of osmium and iridium (usually containing small amounts of rhodium and platinum); used in needles and pen nibs etc. | Synonyms: iridosmine |
|---|
| osmium | (noun) a hard brittle blue-grey or blue-black metallic element that is one of the platinum metals; the heaviest metal known | Synonyms: atomic number 76, Os |
|---|
| osmoreceptor | (noun) sensory end organ that responds to changes in osmotic pressure | - |
|---|
| osmosis | (noun) (biology, chemistry) diffusion of molecules through a semipermeable membrane from a place of higher concentration to a place of lower concentration until the concentration on both sides is equal | - |
|---|
| osmund | (noun) any fern of the genus Osmunda: large ferns with creeping rhizomes; naked sporangia are on modified fronds that resemble flower clusters | Synonyms: flowering fern |
|---|