boron borolanite • boronatrocalcite · · · Info · Definitions · Synonyms · Characters · · boron · · Text Latin · · Script 5 · · Length Definitions · · · (noun) a trivalent metalloid element; occurs both in a hard black crystal and in the form of a yellow or brown powder. Synonyms: B, atomic number 5. · · Noun Definition 1 Synonyms · · · b · · Synonym 1 atomic number 5 · · Synonym 2 Characters · · b latin small letter b U+0062 n latin small letter n U+006E o latin small letter o U+006F r latin small letter r U+0072