Question: I'm currently working on my bachelor thesis in the major of Information Systems and I'm coding a small tool, which analyses other programs based on pre-defined conditions. 

So now I'm looking for an English noun, which describes **"an object that fulfils a condition"**. 

For example a condition could possibly check the type of an object. Like "is object x of type Integer?". I'm looking for a noun describing *x*.

Is it possible to use the word *"trigger"* or something like *"fulfiller"* in this context? 

Which word fits best?

Answer: 
Nouns like *trigger, fulfiller, satisfier* all have problems as words to describe *x* in the question “Is object *x* of type Integer?” or in similar questions. In the question as just shown, *x* is a ***[formal argument](http://en.wikipedia.org/wiki/Function_argument#Parameters_and_arguments)*** or ***formal parameter*** that stands for a name or value to be filled in whenever the question is instanced.

In a specific question instance, where *x* has been replaced with some object or an object identifier, then the candidate object or its identifier might be called a ***solution*** (as previously suggested) if it obviously satisfied the predicate, or might be called a ***candidate*** or a ***putative solution*** or ***proposed solution*** if it's less obvious.

In the somewhat-analogous case of [molecular docking](http://en.wikipedia.org/wiki/Docking_%28molecular%29), the following terminology is used:

> 
> *Receptor* or *host* or *lock* – The "receiving" molecule, most commonly a protein or other biopolymer.  
> 
> *Ligand* or *guest* or *key* – The complementary partner molecule which binds to the receptor.
> 
> 
> 

By analogy, one might refer to predicates as receptors, hosts, or locks, and to corresponding candidates as ligands, guests, or keys. Extending the analogy slightly, a candidate might be referred to as a ***[supplicant](http://en.wiktionary.org/wiki/supplicant#Noun)***.
The common term used in mathematics and other related subjects is "***satisfies***". A condition is satisfied by an object or when an event occurs and produces a certain outcome. 

That which satisfies the condition is the solution (or the root of the equation depending on the context). You can also say "best fit". 

I can help you better if you can reference a couple of sentences that occur before the sentence in which you want to use the word and a couple of sentences that occur after.