writer's block

Reader's Digestに毎月掲載されているNury Vittachi氏の記事Unbelievableは副題にTrue Tales from Asiaとありますが、誇張が過ぎていて余り信用できません。
それはさておき、９月号の記事に出てきた表現が気になりました。
I once managed to get a couple of months' grace from a particularly terrifying landlord by sending him an unsigned cheque. When he got round to asking why it was unsigned, I told him I had writer's block.
以前 "writer's cramp" (10/6/2008) を採り上げましたが、上の "writer's block" はどんな意味があるのでしょうか？　辞書を見ます。
・Oxford English Dictionary: The condition of being unable to think of what to write or how to proceed with writing.: Some call it writer's block, others, cruelly, call it a lack of creativity.
・Merriam-Webster's Online Dictionary: the problem of not being able to think of something to write about or not being able to finish writing a story, poem, etc. 作家がスランプに陥り書けなくなることですね。