Formal/Professional:
* Exposition: A detailed explanation or description.
* Discourse: A formal discussion or presentation.
* Lecture: A formal talk delivered to an audience.
* Address: A formal speech delivered to an audience.
* Demonstration: A display of how something works or is done.
* Briefing: A concise report or explanation.
* Report: A formal account of a situation or event.
* Show: A public exhibition or performance.
Informal/General:
* Talk: A conversation or speech.
* Discussion: A conversation or debate.
* Exposition: A detailed explanation or description.
* Display: A public showing or exhibition.
* Show-and-tell: A informal presentation where someone shows and describes something.
* Pitch: A persuasive argument or proposal.
* Delivery: The act of giving a presentation.
Specific to a particular field:
* Paper: A written report or essay, often presented at a conference.
* Poster: A visual display used to present information.
* Proposal: A formal offer or suggestion.
The best synonym to use will depend on the specific context and the intended meaning.