Learn English – What’s the difference between “reliable” and “dependable”

I see very little difference between the two:

terminology |ˌtərməˈnäləjē| noun ( pl. -gies) the body of terms used with a particular technical application in a subject of study, theory, profession, etc. : the terminology of semiotics | specialized terminologies for higher education.

nomenclature |ˈnōmənˌklā ch ər| noun the devising or choosing of names for things, esp. in a science or other discipline. • the body or system of such names in a particular field : the nomenclature of chemical compounds. • formal the term or terms applied to someone or something : “customers” was preferred to the original nomenclature “passengers.”

Based on these definitions from NOAD, terminology seems a little broader, that is all, while nomenclature seems more systematic and deliberate.

Vague means that the information is lacking in detail - if you give a vague description of something, the listener/reader won't be able to imagine the subject with much precision.

Unclear could mean the same but also might suggest that the information is confusing, either as a result of poor use of language or perhaps through contradicting information.

Ambiguous is when something can have more than one meaning or refer to more than one subject and the listener/reader might have difficulty knowing exactly what it is you are describing.