Is there a connection between the various "states of being" that you can be "on"?

Prompted by the title of this question and a couple of comments on it, I'm minded to think there that many "states of being" that you can be "on", as in...

on fire, on holiday, on guard, on the blink (intermittently faulty), etc.

Sometimes we just use [verb]ing to generate an appropriate word (holidaying, guarding, resting, etc.)

Or different prepositions (in purdah, at play, under suspicion, etc.)

Is there a (even partially-applied) rule indicating when on should be used?

Just to muddy the waters a bit (or maybe it'll inspire someone to see the rule, I dunno). You're at lunch, but on your lunch-break.

By way of one final 'tickle', I wonder if the difference between in retreat and on retreat will spark a line of thinking in someone ("in..." meaning "running away", whereas "on..." probably implies you're spending some time at a monastery or similar).


I really don't think that there is a rule. and if there is one, I've never heard of it. These are all idiomatic expressions, which by definition have a meaning which isn't derived from the meaning of their components.


I came up with some various states of being that we use with prepositions. I then alphabetized them to group them by preposition. Since the linguistic rules are usually encoded in our brains and not written down, linguists have to infer what the encoded rules might be.

  • awake
  • asleep
  • at a party
  • at attention
  • at ease
  • at my desk
  • at play
  • at the point of no return
  • at work
  • in a jam
  • in a pickle
  • in line ("on line" in New York and UK)
  • off duty
  • off the grid
  • on a roll *
  • on break *
  • on drugs
  • on fire *
  • on guard
  • on tip toes / on his toes *
  • on line ("in line" when not in New York or the UK)
  • on pins and needles *
  • on the blink *
  • on the fritz *
  • on the house ("free") *
  • on the pill
  • on time *
  • on track
  • on vacation *
  • online (electronically attached)

Some of the "on" prepositions seem to fall into a category of the contrast of on/off. Consider:

  • on duty / off duty
  • on guard / off guard
  • on track / off track
  • on grid / off grid
  • on drugs / off drugs
  • on the pill / off the pill
  • online / offline

(I have starred the "on" states of being from the first list that do not fall into an on/off category.)

But why not on the blink / off the blink? These idioms are probably too hard to reverse ("off the blink" would mean "working consistently"). Why not on fire / off fire? Perhaps because "on fire" or "afire" are already linguistically indicated: it is an unusual state for something to be on fire. Note that if it is the normal state for something to be on fire, we don't use the phrase "on fire," we use "on" or "lit." (For example, you don't say that the stove is "on fire" if someone left a burner on. When you say, "The stove is on fire," you would probably need to call the fire department and evacuate the house.)

Same reasoning for on vacation / off vacation. "On vacation" is the indicated form, because "at work" is where we are for 90% of the time.

I would propose the "on" rule as:

Use "on" when the state-of-being implies that the subject is following a normal course of action.

So for the second list,

  • on duty = I am in the state of working
  • on guard = I am in the state of guarding
  • on track = I am in the act of tracking
  • on grid (No, this one doesn't work, perhaps because "on grid" is the less-indicated state)
  • on drugs = I am following the course of taking medications
  • on the pill = (same)
  • online / offline = I am in the act of communicating with an electronic device

The other starred items (e.g., "on his toes," "on the fritz") have a very idiomatic feel to them, at least to my ear.

I could use some help in improving the rule, which I am sure the SO community will be willing to provide.