what does 'to have and to hold' mean?

What is the literal definition of this? Is it a polite way of saying,
have sex, be intimate?

This is a very interesting question.
First, to your second question:  no, I don?t believe it refers to the
right to sex for a couple of reason.
I think this was/is tacitly understood in any wedding ceremony, or
somewhat explicitly stated in those that include(d) the phrase: 
?become one flesh.?
The expression ?to have and to hold? is a common law term that occurs
in other types of contracts, especially in those granting use of real
property.

To understand this, one needs to go back centuries in English law to
the time of fiefdom when it was understood that all land belonged to
the king and only was assigned by him ?to have and to hold? by
someone, maybe for life, maybe also to his heirs, i.e., in perpetuity.

The expression suggests the pairing of two other legal expressions:
ownership and possession.
(If you rent or lease something, you have legal possession but not ownership.)

?To have and to hold? in such contracts, however, defines the right to
possession and the obligation to use and maintain the property: defend
the right to it against others, keep and preserve it.

Okay, in marriage vows, this may still sound like subjugation of the
wife, but it should be noted that the expression traditionally is/was
spoken by both bride and groom:  here, an example:

?I, (Bride/Groom), take you (Groom/Bride), to be my (wife/husband), to
have and to hold from this day forward, for better or for worse, for
richer, for poorer, in sickness and in health, to love and to cherish;
from this day forward until death do us part.?

The subsequent phrases emphasize that the vow ?to have and to hold? is
an obligation to support the partner regardless of what fate may
bring.
Here is the full text of the wedding ceremony in the Book of Common
Prayer of the Anglican (English) church.
http://www.weddingtips.com/wedding-vows/common.html

This article gives an earlier version of English wedding vows.  Note
in the indented lines following the first paragraph of the ?Breviary?
section that the expression is followed by  ?at bed and at board,? 
i.e., the vows add the detail that the partner must be housed and fed.
 Again, this sounds like an obligation towards chatteled servants, but
the folks in York at the time must have known why they felt it
necessary to include this in wedding vows.
http://en.wikipedia.org/wiki/Use_of_York

Here are two sites with modern use of the expression in lease
contracts.  Notice in the first one the details about maintenance of
the property.
http://www.lectlaw.com/forms/f165.htm
http://www.allaboutlaw.com/index.cfm?index=forms122a&topic=24&form_topic=Deeds&CFID=1332909&CFTOKEN=23337

And here are two sites showing medieval legal use of the expression. 

http://www.constitution.org/sech/sech_071.htm
http://www.historicaldocuments.com/MagnaCarta.htm

I hope this helps.

I think it's one of those rare instances where you get to have your
cake, and eat it too, --as long as it's that same cake...

The latin phrase is 'habendum et tenendum' and is known on legal
contracts as the Habendum Clause. I cannot find much more information
than that usefully provided by myoarin-ga; and no information as to
how it came to be part of the marriage vows - perhaps it is because
marriage is a publicly announced contract between two people, both of
whom probably bring their own property into the marriage to be shared
between them.


?Habendum Clause is the 'to have and to hold' clause in deeds and
mortgages. The habendum clause comes from the Latin phrase 'habendum
et tenendum', meaning 'to have and to hold'. This clause or series of
clauses (as the case may be) in any instrument of conveyance (a deed)
defines the type or extent (ie. limits) of the amount or quantity of
estate granted in the deed premises. The habendum clause states the
owner's exact interest in the property or extent of title. ?
http://www.mortgagefit.com/habendum-clause.html

http://books.google.com/books?ie=UTF-8&vid=0kW346vLl1nJUrxZX1X&id=ZcRBc4OCjGIC&num=10&pg=RA3-PA212&lpg=RA3-PA212&dq=%22to+have+and+to+hold%22+contract