The British navy used to afford each sailor a ration of rum per day of a voyage to lift morale and prevent mutiny. This nautical tradition still carries on strong to this day, with a "rum ration" used as a term to describe a range of fringe benefits. Some companies (Scottish and English) still give sailors an actual rum ration whilst at sea whilst some companies with a nautical tradition (even though they may now deal in other business) give their employees a payment in "kind" in lieu of a rum ration. A good example is the Royal Bank of Scotland (formerly brokers for shipmen and traders) who, to this day, still give out a "rum ration" in the form of a free beef filled "bampot" every lunchtime and a leg of lamb or a ham shank for the employees table every other weekend.
As well as describing the drink. the word "rum" can be used to describe something that may be amiss. For example, "gay marriage, that sounds a bit rum.