What is the best way to find out if a certain phrase is considered a cliché?
Is there an online resource, a specialized dictionary-like lookup?
I found these so far:
TvTropes is a good place to find them, if you don't mind some investment of time. Alternatively, a site specific search may give you additional insight: TvTropes loves to abuse cliches and puns, and if a quick google for 'site:tvtropes.org phrase here' showed a whole bunch of results, the chances are fairly good that this is a cliche.
Wikipedia has a very limited list: http://en.wikipedia.org/wiki/Category:Clich%C3%A9s
As far as an online cliche dictionary/thesarus, I don't know of any.
Probably the best way would be to use the Google Ngrams viewer, which lets you track the usage of given phrases or words through Google's vast collection of scanned books. What it does is give you a percentage of the total usage of that phrase versus usage of all phrases of that word length in any year Google has data. The date ranges go back to the 1400's or so. You could compare a phrase to multiple other phrases and determine if it appears significantly more than other phrases with the same meaning and probably guess that it is a phrase, but this wouldn't always hold true. For instance, 'it was raining that night' far outpaces 'it was a dark and stormy night' in total usage, but 'it was a dark and stormy night' is widely recognized as a cliche.
What is and isn't a cliche is pretty subjective, so I don't think there is any kind of definite answer. Certain genres may have unique cliches, eg. Science fiction would have differing cliches (aliens invade the Earth) versus romance (Romeo and Juliet plot).
Maybe you could provide an example case? If you wanted to avoid cliched phrases in your writing to appear more professional, a good editor should be able to assist you in this.
Check out my program ClichéCleaner.
It highlights passages in your text that are either clichés, other overly-used common expressions, or phrases of your own that you have repeatedly used within the same document.
ClichéCleaner includes a list of nearly 7000 unique clichés and common expressions that are compared against your text. However the actual number of phrases compared against totals over 16,000 counting all the variations. For example, when searching for the cliché "lose one's shirt," the various verb forms lose, lost, and losing are all checked, as well as his, her, my and your being substituted for "one's". That's 15 different versions of just this one cliché!.
It currently just works with just text files (or any text pasted into its editor window); however I am working on a version that will allow native checking and editing of MS Word files.
I wrote this program myself, I hope it is okay to post a link to it here since it appears to be on-topic.