What's the difference between warehouseman and warehousemen?

Warehouseman

Definition:

(n.) One who keeps a warehouse; the owner or keeper of a dock warehouse or wharf store.
(n.) One who keeps a wholesale shop or store for Manchester or woolen goods.

Example Sentences:

(1) A warehouseman aged 31 working in a pharmaceutical factory got an occupational contact dermatitis to virginiamycin (factor M), an antibiotic used as a food additive for pigs and poultry.
(2) Differences according to occupational category are very important: between the occupations the most prone to absence, those of "switchboard operator", "mechanics driver" and "warehouseman" and the ones least exposed "managerial staff" and "skilled technician and upper management", the ratio for the prevalences was 10.
(3) The inclusion of Kelman – a former warehouseman, care worker and local government administrator – will give hope to budding novelists.

Definition:

Example Sentences:

(1) West and east Indian trade founded merchant dynasties, but also created a hinterland of ship builders, outfitters, victuallers, warehousemen, carriers and wholesalers.