bromide

noun

1. A binary compound of bromine and some other element or radical.
2. A dose of bromide taken as a sedative, or to reduce sexual appetite.
3. (by extension) A dull person with conventional thoughts.“My adviser at college was a bromide who had not had an original thought in years.”
4. A platitude.“We hoped the speech would include reassurances, but instead it was merely one bromide after another.”