WordNet sense 1 (an event that occurs when something passes from one state or phase to another):

alteration, modification

WordNet sense 2 (a difference that is usually pleasant):

variety

WordNet sense 3 (give to, and receive from, one another):

exchange, interchange

WordNet sense 4 (change from one vehicle or transportation line to another):

transfer, transfer

WordNet sense 5 (become deeper in tone):

deepen

WordNet sense 6 (lay aside, abandon, or leave for another):

shift, switch

WordNet sense 7 (exchange or replace with another, usually of the same kind or category):

commute, convert, convert

WordNet sense 8 (cause to change; make different; cause a transformation):

alter, modify

WordNet sense 9 (make or become different in some particular way, without permanently losing one's or its former characteristics or essence):

vary