The Customer service person does not understand client language. How the language effect on customer services?

Working in any industry we use a certain abbreviation to make our lives and work progress faster. However, we tend to forget that when we are communicating with clients they may be unfamiliar with those abbreviations. A lot of times they don't want to clarified so they wont come across as unprofessional or not well informed. It is important to avoid that so we won't ruin the relationship.