adjective / noun
formative
FOR-muh-tiv/ˈfɔːrmətɪv/
Helping shape something during its development.
The curved frame has a formative influence on the growing tree.

Etymology
Formative describes something that serves to give shape. Applied to development, the shaping is figurative: an experience or influence helps determine the character of a person or thing.
In context
It was very formative and influential for me. He brought me in touch with important persons for my further development.
More examples
- Her grandmother's stories are a formative influence on her values.
- The teacher uses formative assessments to adjust each lesson.
- In this word, the prefix is a formative.
Forms
Similar words
- influential
- Emphasizes an effect on others, not specifically their development.
- developmental
- Relates to growth without necessarily helping shape its course.