Variable: org-drawer-regexp
org-drawer-regexp is a variable defined in org.el.gz.
Value
"^[ ]*:\\([_[:word:]-]+\\):[ ]*$"
Documentation
Matches first or last line of a hidden block.
Group 1 contains drawer's name or "END".
Source Code
;; Defined in /usr/src/emacs/lisp/org/org.el.gz
;;;; Drawer
(defconst org-drawer-regexp
;; FIXME: Duplicate of `org-element-drawer-re'.
(rx line-start (0+ (any ?\s ?\t))
":" (group (1+ (any ?- ?_ word))) ":"
(0+ (any ?\s ?\t)) line-end)
"Matches first or last line of a hidden block.
Group 1 contains drawer's name or \"END\".")