Involving, relating to, or emphasizing behaviour. ‘closely related species have similar behavioural patterns’. ‘a behavioural approach to children's language’. ‘Patient-doctor relationships are generated by different behavioural patterns.’. ‘Food in the stomach does not appear to alter the kinetics or behavioral effects of the medication.’. ‘In the end the sound of the bell alone was enough to bring about a behavioural response - the dog began drooling.’. ‘Prey show the same response, regardless of the behavioral state of the predator.’.