bradykinin UK /ˌbɹæd.ɪˈkʌɪ.nɪn/US /ˌbɹeɪ.dəˈkaɪ.nɪn/ noun1 •A compound released in the blood in some circumstances which causes contraction of smooth muscle and dilation of blood vessels. It is a peptide with nine amino-acid residues. formsbradykinins
