The Khazad: Custodians of Hidden Hoards by Arden R. Smith (Vinyar Tengwar #18, p.26)

The English word hoard (OE hord OHG hart, ON hori, Goth huzd) comes from Gmc. *huzdam (Watkins 60),*huzdo- (de Vries 246, Drosdowski/Grebe 273) or *huzdo- (Skeat 242) with the original meaning 'thing hidden away'. Is it merely coincidental that the Khuzdul root KhZD referring to the secretive and avaricious Dwarves, seen in Khazad-dum, Khazad (early version Khuzud, LR, 274, 278), and Khuzdul, should be so similar in form? 

The Germanic word supposedly comes from an Indo-European suffixed form meaning 'a thing hidden', *kudh-to> *kud-dho- *kud`-dho-(Prokosch 84); * kudh-to- (Watkins 60);   kudh-dho- (Buck 778, Skeat 242); or * kus-dho- (Buck 778, Watkins 60), whence also Gk. reaBor. 'concealed place, female organ' and Lat. curios 'guardian', lit. 'hider'. Like the verb hide, it derives ultimately from an Indo-European root meaning `to cover', *(s)keu- (Buck 778, de Vries 246, Drosdowski/Grebe 273, Watkins 60) or KEUDH (Skeat 242). 

Accepting the derivation of hoard and its Germanic cognates from this Indo-European root as fact (though this etymology could theoretically be inaccurate), the derivation of the Germanic words from Khuzdul would have to be by way of Indo-European. This is, however, considerably more problematic phonetically than a loan from Khuzdul directly into Germanic. Perhaps a merging of the Dwarvish and Indo-European roots can be assumed. Whether or not Tolkien intended a linguistic relationship between Khuzud/Khuzdul and huzd, it seems likely that this was his inspiration for the KhZD root. 

Bibliography

Buck, Carl Daning. A Dictionary of Selected Synonyms in the Principal IndоEuropeаn Languages. Chicago: University of Chicago Press, 1949. 

de Vries. Jan.Altnordisches etymologisches Worterbuch. Seconded. Leiden: E.J.Brill,1962. 

Drosdowski, Gunther, Paul Grebe, et al. Duden Etymologie: Herkunftsworterbuch der deutschen Spraehe. Mannheim/Wien/Zurich: Bibliographisches Institut, 1963. 

Prokosch, E A Comparative Germanic Grammar. Philadelphia: Linguistic Society of America, 1939.

Skeet, Walter WA Concise Etymological Dictionary of the English Language. Oxford' Clarendon Press., 1882. 

Watkins. Calvert, ed. The American Heritage Dictionary of Indo-European Roots. Boston. Houghton Mifflin, 1985.