autosuggestionist
/ˌɔːtə(ʊ)səˈdʒɛstʃ(ə)nɪst/ /ˌɔːtəʊsəˈdʒɛstʃənɪst/Now rare
noun
A person who induces or is susceptible to autosuggestion.
Origin
Late 19th century; earliest use found in Popular Science Monthly. From auto- + suggestionist, after French auto-suggestionniste.