Is "hold out a promise" the same meaning as "make a promise"? Or did I misunderstand them? I found definitions for "make a promise", but couldn't find definitions for "hold out a promise".
Jon is correct, and I am such a beginner that I hesitate to horn in here, and I do so only to make certain that the answer is absolutely clear. Please pardon the intrusion.
It's a bit confusing because there are two verbs used, but neither is used as they normally are. "Make" a promise? "Hold" out a promise?
To make a promise is a common expression meaning that you have vowed to another person that you will follow through on certain matters, such as your intent to marry her, or clean the front yard, or go grocery shopping. It is a direct declaration between two or more people.
On the other hand, to hold out a promise refers to a situation that appears to point to a particular conclusion, that a promise will end in a certain way. The three-week-old milk bottles held the promise of containing rotten milk, so we threw them away.
Something can "hold promise," meaning that it may offer the prospect of beneficial but not yet realized consequences. A person may "withhold a promise," meaning that the person declines to become duty-bound to perform something. And of course a person can "hold out X" in the sense of extending X in his or her hand. But the phrase "hold out a promise," I think, lies in a murky realm of its own, apart from those relatively clear alternatives.
The likeliest intended meaning of any contextless instance of "hold out a promise," in my opinion, is the meaning that I gave above for "hold promise." But it's at least possible that the speaker/writer intends the phrase in the sense of dangling the possibility of a future promise in front of someone, without committing to it in the present. Or again (as you suggest) the person could simply mean "make a promise." In any event, the wording as given is both inherently confusing and readily avoidable, which are two good reasons not to use it.
EDIT (2/16/13): To follow up on the "dangling a promise" meaning of "hold out a promise," I note that two of the first three unique Google results for "hold out a promise" are as follows:
From a sermon by Joshua Brooks in Essays on the Advent and Kingdom of Christ: And the Events Connected Therewith (1840):
My brethren, among ourselves at this present time there is a transaction going forward; a great transaction of business for eternity. Temptations abound. Fraud holds out a promise of gain. Unfaithfulness holds out a promise of ease. Vanity holds out a promise of distinction. Unbelief holds out a promise of impunity.
From a Denver Post story, "Getting a day of rest powerful for even the nonbelievers" (September 3, 2011):
Technology holds out a promise of unlimited accomplishment and efficiency, but experts say it's a false promise that's encouraging us to drive ourselves crazy.
In both instances, the author's focus on the dangling of the promise serves immediately afterward to underscore the falseness of the promise.
I would have thought this was a general reference, but an attempt to find such a reference has failed, so I'll answer instead.
It's close to "make a promise", but "make a promise" generally means promise in the sense of a declaration that one will do (or refrain from doing) something. (The similar "hold [someone] to their promise" means to insist that that promise be kept).
"Hold out a promise" uses promise in the sense "a reason to expect something".
So if I said "the government made a promise that the tax changes would increase exports" that means that they actually said that exports would increase.
Whereas if I say "the tax changes hold out a promise of increasing exports," that means that I believe that exports will increase.
People make a promise. Anything, including people, but mostly conditions and events, hold out a promise.
It's not the same meaning. In make a promise, the meaning applicable is,
a declaration or assurance that one will do a particular thing or that a particular thing will happen:
what happened to all those firm promises of support?
[with clause]: he took my fax number with the promise that he would send me a drawing
[with infinitive]: I did not keep my promise to go home early
and in hold out a promise,
[ibid] the quality of potential excellence: he showed great promise even as a junior officer
[in singular] an indication that something specified is expected or likely to occur: the promise of peace
Three open, trumpet-shaped flowers suddenly burst open on our plant, and a fourth was still tightly closed, but held promise. Vignettes of Life in Charleston, Sc p288
She argued that animal cloning held promise for medical research, including the development of new drugs and animal organs for transplantation, and she urged lawmakers not to restrict promising science when proscribing human cloning. From Dolly to Stem Cells p34
The lanky, razor-sharp 18-year-old Scottish tennis player Andrew Murray dropped out of Wimbledon after a valiant struggle yesterday, but - for the crowd that had massed to cheer its new hero - the finish held little sting: Murray's defeat was of the unusual kind that holds the tantalising promise of victories to come. Even bitter defeat held promise of victories to come