Is 'hypothecate' anything to do (in origin or meaning) with 'hypothetical'?

I had never come across the word before but apparently a hypothecated tax is one in which ring-fenced funds are collected by taxation to pay for a specific government expenditure. This kind of tax is being suggested in the UK in order to fund the National Health Service in the future.

The OED appears to be defining the verb 'hypothecate' in a way that is definitely different in meaning to 'hypothetical' :

  1. trans. To give or pledge as security; to pledge, pawn, mortgage.

'Hypothetical' is from 'hypothesis' which the OED tells me comes from Greek : ὑπό under + θέσις placing. So a hypothesis is an argument 'placed under' a statement.

The OED gives the etymology of 'hypothecate' as :

hypothēcāt-, participial stem of medieval Latin hypothēcāre , < hypothēca hypothec n.: see -ate suffix3. Compare French hypothéquer.

But this all seems a bit muddled to me both in the origin (would not 'hypothecate' have a Greek etymology, intially ?) and in the present English meaning (is not the ring-fenced tax an opposite of a hypothetical tax ?).

It is especially odd when the OED then offers a second meaning for 'hypothecate' as :

  1. trans. = hypothesize v. 2.

thus implying either the same origin or the same meaning for the word as 'hypothetical'.

Any help would be appreciated.


The answer to the origin and meaning lies in the Greek root given by Etymonline, where they distinguish between θεκε, theke and θεσις, thesis, as the Greek roots of 'hypothecate' and 'hypothesis'.

θεκε, theke, is a containment of some kind or a building (apotheke is a barn, Strong 596). So 'υποθεκε, hupotheke, is that which, metaphorically, is under a building - namely the pledge or mortgage.

Therefore, to hypothecate is, historically, to lay something down, financially, to support the purchase of a building.

Whereas to hypothesize is to lay down an argument in order to support a theory about experimental evidence or observed phenomena.


To hypothecate is to lay down money as a pledge.

To hypothesize is to lay down a theory beneath data or phenomena.


NOTE : It was @user159691 who drew attention to the Greek roots by providing the reference to Etymonline in an answer which, for some reason, is now deleted.



Indians are very familiar with the word, though we never bothered to find its origin.Transport vehicles bought on bank loan in India are required to have a shout box with the phrase "hypothecated to so and so bank". It just means the chap has pawned his wife's gold ornaments or his family property to buy a work truck. Growing up, I couldn't help reading every one of those, while waiting in a traffic jam. Its a 'hard to miss' word, if you drive in India. Many wouldn't know the name of the current President but would've heard this word.