The Texinfo export back-end supports two approaches to writing Texinfo definition commands. One of them is described here, the other in Plain lists in Texinfo export.
The Texinfo export back-end converts special blocks to commands with the same name. It also adds any ‘:options’ attributes to the end of the command, as shown in this example:
#+ATTR_TEXINFO: :options org-org-export-to-org ... #+BEGIN_defun A somewhat obsessive function name. #+END_defun
becomes
@defun org-org-export-to-org ... A somewhat obsessive function name. @end defun