Exchange
Part of speech: noun
Definition: An act of exchanging or trading. A place for conducting trading. (telephony, US only?) The fourth through sixth digits of a ten-digit phone number (the first three before the introduction of area codes). A conversation.
Part of speech: verb
Definition: To trade or barter. To replace with a similar item.
Example sentence: Ideal conversation must be an exchange of thought, and not, as many of those who worry most about their shortcomings believe, an eloquent exhibition of wit or oratory.
Change
Part of speech: noun
Definition: the process of becoming different.small denominations of money given in exchange for a larger denomination.a replacement, e.g. a change of clothesa change-up pitchmoney given back when a customer hands over more than the exact price of an item.
Part of speech: verb
Definition: To become something different.To make something into something different.To replace.To replace one's clothing.To transfer to another vehicle (train, bus, etc.)
Example sentence: Only the wisest and stupidest of men never change.