The acronym TRN has multiple meanings depending on the context. Here are some of the most common definitions found in the search results:

• Transcriptional Regulatory Network: A network of genes and their regulatory interactions that control gene expression.
• Temporary Routing Number: A tracking number issued by the Department of Public Safety upon an arrest.
• Training Resource Network: A company that provides training and development services.
• Total Return Net: A financial term that refers to the total return on an investment after accounting for expenses and fees.
• Taxpayer Registration Number: A unique identification number assigned to taxpayers in Jamaica.
• Threaded Read News: An internet chat term.
• The Resource Network: A miscellaneous term.
• Terrain-Reference Navigation: A navigation system that uses terrain data to determine position and orientation.
• Target Reference Number: A term used in military and defense contexts.
• Task Requirement Notice: A term used in military and defense contexts.
• Trashy Romance Novel: A term found in Urban Dictionary.

It is important to note that the meaning of TRN can vary depending on the context in which it is used.