IPA: /ɪnˈstɪlər/
KK: /ɪnˈstɪlɚ/
A person who teaches or introduces ideas, feelings, or values gradually and carefully.
The teacher was an instiller of confidence in her students.
Instiller → It is formed from "in-" (meaning into) and "stillare" (meaning to drip or let fall). The word describes the action of causing something to flow or drip into something else.
Think of something 'dripping into' ('in-') another substance ('stillare') — that's why instiller means to introduce a substance gradually.