| Word | Definitions | Synonyms |
|---|---|---|
| boron | (noun) a trivalent metalloid element; occurs both in a hard black crystal and in the form of a yellow or brown powder | Synonyms: atomic number 5, B |
| borosilicate | (noun) a salt of boric and silicic acids | - |
| borough | (noun) one of the administrative divisions of a large city | - |
| (noun) an English town that forms the constituency of a member of parliament | - |