modify B1

/ˈmɑ.dɪˌfaɪ/ To change something slightly, especially to improve it.

modifiable C2+

/ˈmɑdəˌfaɪəbəl/ capable of being changed or altered

modifier C2+

/ˈmɑdəˌfaɪər/ a word or element that qualifies or limits the meaning of another