Jobless comes from 'job' + the native suffix '-less' ('without'); 'job' is of obscure origin, perhaps from obsolete 'job' ('a lump, piece'), the original sense being a piece of work. The etymological trail includes Old English -lēas. As an adjective, jobless means without paid employment; unemployed. The same family is visible in derived forms such as joblessness and related forms such as job. Morphologically, the word is built from the elements named in its history, so the modern form preserves a visible compound, prefix, or suffix structure. The uncertainty belongs to the older derivation, so the explanation should preserve alternatives rather than choosing one unsupported origin.