Jargon: Special words or expressions that are used by a particular profession or group and are difficult for others to understand
Speaking in jargon is a presentation hazard faced by technical or highly educated speakers. A speaker can be so involved with a subject that he doesn’t even notice that he is doing it; jargon is just his native language.
In general, anything that distracts from the audience focusing on your message should be avoided. When a listener hears an unfamiliar word, phrase, or acronym, part of their brain will be trying to decipher what that means. That distracts them from what you are saying next. So comb through your speech, looking at it through the lens of someone new to your subject.
That said, in speaking to people in your field who speak your language, jargon is more appropriate. If you find yourself in need of some useful jargon, particularly in the fields of philanthropy and development, there is a tool that will help you find the right words. Use this for any occasion! Jargon Generator