It was appalling to hear the CEO of AT&T say, when he was referring to on-site products the company sells:
“premise equipment.”
It was equally shocking to see a software company Web site list the following:
“Solutions are available both on-premise and OnDemand.”
Where are the Grammar Police in corporate communications? Yikes!
Here’s today’s lesson …
premise. n. a previous statement serving as a basis for an argument; a proposition helping to support a conclusion.
And, premise may also be used as a verb, however, we won’t get into that here.
Now, one could have more than one thought or premise. In this case, the plural would be regular … just add an “s” to get premises.
That leads us to a “totally different” word:
premises. n. a piece of real estate; a tract of land including its buildings; a building together with its grounds or other appurtenances.
We know it may seem illogical, using a seemingly-plural word to speak about a location, BUT …
How many seemingly-illogical rules are there in the English language?
The thing is … premises, when referring to location, is both singular and plural. This is an important rule to remember.
Therefore, the premise that this entry is incorrect, is incorrect:
Thanks to pomphorhynchus for this great example.
Never, never (at the risk of doing time in the GrammarGallows) drop the last “s” from premises when speaking of location!
Now you know. Take a look back at the dreadful offenses with which we started this post. Recognize the errors?
We presume you have read this entry. Based on that premise, we conclude that when you are at home today, you will know that you are on your premesis!
Grammar Police a.k.a. GrammarCops 
Um, a point of diction: the above egregious error is a one in diction, not grammar.
I’ve been trying to get the attention of the Zoës Kitchen restaurant chain, but they won’t listen. Each bottle of their Greek Dressing continues to sport a label that insists it was “made on the premise.” They won’t explain the premise on which it was made.
We have had this question of several dry cleaning establishments professing that their dry cleaning is “done on premise”.
By the way, we presented this post on the premise that diction (noun: def. style of speaking or writing as dependent upon choice of words) is a sub-set of grammar (noun: def. the study of the way the sentences of a language are constructed; morphology and syntax).