Telchar is the Dwarven smith of Tumunzahar (Nogrod) that created the sword Narsil, among other works. Most people see the <ch> in the name interpret this name as being Elven in origin. However, doing so is a real stretch, and I haven't seen a credible etymology for it yet. I explained in the page about the consonant inventory why <ch> is most probably a consonant in Khuzdul. The other names of Dwarves of the Ered Luin, Azaghâl and Gamil Zirak, are obviously Khuzdul, so seeing Telchar as Khuzdul also shouldn't be an issue. In fact, the presence of the other two names being Khuzdul makes it more likely that Telchar is Khuzdul as well.
Tolkien never gave a translation of the name, or a gloss. Assuming Telchar is a Khuzdul name, it might be viewed as odd that Tolkien gave no explanation of <ch> in Khuzdul in Appendix E. He did say that Khuzdul "did not possess the sound represented above by th and ch (kh)", but that means that Khuzdul did not have the voiceless palatal fricative [x], which is represented by <ch> in Sindarin. It could be that Telchar's name appears only once in The Lord of the Rings, so it was simply an oversight. English speakers reading the name would tend to pronounce it close to correctly anyway without guidance. On top of that, Dwarvish words starting with <kh> were "softened" to <h> when imported to Sindarin, and the mostly likely change for Khuzdul's <ch> ( IPA: [tʃh] ) in Sindarin is to become the voiceless velar fricative [x], which is also represented by <ch>! With this being the case, it doesn't seem that you can say with any surety whether Telchar is one language or the other, simply by the presence of <ch>.
In The Silmarillion, pg 94, Telchar is referred to as "Telchar the smith". Although this may be scanty evidence, we could follow the example of "Gamil Zirak the old" and say that Telchar is also a descriptive name (laqab) and means "smith". As it happens, we can find some support for this in that Arabic uses a t- prefix for some verbal roots to indicate an agent, especially as a profession. Taking this, we could see a root L-Ch-R "to smith, forge". From there, a verb lecher "to smith, forge" might follow the pattern of felek. After felak, a lechar would be a "thing that smiths, forges"; so basically, a "forge". The profession would then use the t- prefix to form telchar "smith". Surely, if any Dwarf in the history of Middle-earth deserves the descriptive name "smith", it would be Telchar!
Telchar then is, until more evidence comes along, "smith" and is singular, nominative, indefinite.
The Silmarillion, pg 94, 177