* Comp. - This is the most common abbreviation for "compound" used in general contexts.
* Cpd. - This abbreviation is sometimes used in scientific and technical contexts.
* Cmpd. - This abbreviation is less common, but sometimes used.
It's important to note that the context will often dictate which abbreviation is most appropriate. For example, in a chemistry context, "cpd." might be preferred, while in a general writing context, "comp." would be more appropriate.