Verisimilitude
/ˌvɛr.ɪ.sɪˈmɪl.ɪ.ˌtjuːd/ noun hardVerisimilitude is the believable, realistic quality that makes an invented story or scene feel genuine.
The director hired real astronauts as consultants to give the film's space scenes greater verisimilitude.
Memory Trick
Verisimilitude combines the Latin 'veri' (truth) and 'similis' (similar) - it means something is similar enough to the truth to feel real.