[mass noun] The collagen of bones.
- ‘Colla cornus cervi, which contains a large amount of ossein and Ca. + +, plays an important role in preventing bone destruction.’
- ‘The plant will have the licenced capacity to process 13,000 tonnes of crushed animal bones into 3000 tonnes of ossein and 6000 tonnes of dicalcium phosphate.’
Mid 19th century: from Latin osseus bony + -in.
We take a look at several popular, though confusing, punctuation marks.