Changing shape to suit the conditions it meets. Accommodation without loss of identity.
Built on respond, from Latin respondere (to answer): re- (back) + spondere (to pledge); to be responsive is to keep answering back to whatever conditions change, without losing the shape that is answering.
Changing shape to suit the conditions it meets. The root's answering is accommodation without surrender — a responsive thing still keeps its own identity while it keeps replying.