Yes. Although 'privileged communications' with people such as your attorney, doctor, or clergy member, are generally not subject to discovery, no such privilege is extended for entries made in a diary.
(Unless you were preparing the diary, say, at the specific request of your attorney, to keep track of something related to a lawsuit.)
It is spelled Dear Diary.
his diary
Kim's diary = the diary that belongs to Kim
Diary - 2000 Diary of Ludacris was released on: USA: 2002
Who keeps a Diary? The diary was full with secrets.
Diary - 2000 Best of Diary was released on: USA: 1 February 2001
Anne received the diary on her birthday. She wrote about receiving the diary and her birthday and the problems in Belgium and her life.
The most famous diary is Anne Frank's diary.
Her diary is called, "A Diary of a Young Girl".
The plural of diary is diaries.
Diary - 2000 Diary of Tony Hawk was released on: USA: March 2003
Diary - 2000 The Diary of Lindsay Lohan was released on: USA: March 2004