Real Dictionary

out of pocket
phrase: If you are out of pocket, you have less money than you should have or than you intended, for example because you have spent too much or because of a mistake.

out of pocket in American English
having less money than you should have or than you intended, for example because something was more expensive than you expected or because of a mistake
having suffered a financial loss; poorer
used for describing expenses which someone pays out of their own money, and which are normally paid back later

out of pocket in British English
designating unbudgeted expenses, or ready cash paid out, as for miscellaneous items
from money at hand
having lost money, as in a commercial enterprise
having made a loss, as after a transaction
adjective: lacking money
adjective: paid out or owed in cash; necessitating an expenditure of cash

out-of-pocket
Out-of-pocket expenses are those which you pay out of your own money on behalf of someone else, and which are often paid back to you later.