Why is it said that an alarm clock is going off when really its coming on?

Answer 1

The key is that you're not using just the word "off", you're using the phrase "go off" (and in a specific setting). You should not think of each word as somehow functioning on its own... language doesn't work like that.

In fact, you are focusing on ONE meaning/use of the word "off".. It may be one of the more common ones but it is by no means the only one. (In fact, if you want to argue this way, you ought to go with the 'original' physical meaning --describing the position of one object in relation to another.)
Check a dictionary and you will find MANY entries. e.g., 56 at http://dictionary.reference.com/browse/off

Simple, common prepositions and adverbs like this in MANY LANGUAGES may be used in a wide variety of ways, and often take special nuances in specific situations and in combination with with specific verbs.

These combos, called "phrasal verbs", are quite common in English, and provide a useful way of expanding what we can say without inventing entirely new words. It's best to think not of the individual pieces but the combinations as 'separate words' (vocabulary items).

Definition... of "phrasal verb"
"idiomatic expressions, combining verbs and prepositions to make new verbs whose meaning is often not obvious from the dictionary definitions of the individual words. They are widely used in both written and spoken English, and new ones are formed all the time as they are a flexible way of creating new terms."

http://www.usingenglish.com/reference/phrasal-verbs/
http://owl.english.purdue.edu/handouts/esl/eslphrasal.html
http://www.englishpage.com/prepositions/phrasaldictionary.html


(By the way, there are languages which often form COMPOUND verbs -- preposition attached directly to the verb, esp. prefixed to it-- which may function very similarly to our phrasal verbs. Examples: Latin, Greek. But people somehow don't think of these the same way, partly because they recognize it as a separate word when they are combined in this way.

Answer 2

I had a smart answer for you but got to thinking that you are right because the first thing I yell to my husband when the alarm clock sounds is turn that *******alarm off.So if I say turn it off then that means it is on not off.

Answer 3

It's kind of like when you "go off" on someone, you are yelling at them, reading them the riot act, etc. Well, with an alarm clock, it does the same thing when it wakes you up! It is "going off" on you. Otherwise, you wouldn't wake up on time.

Answer 4

True, true, just like a bomb going off, or a person a nswering his own great, and wonderful question, who is not you.

Answer 5

Why does your nose run and your feet smell?