Britain has plenty of lords, but here is the odd part: “lord” is not one of the five ranks of the British peerage.

The actual ranks, from highest to lowest, are duke, marquess, earl, viscount and baron. “Lord” is a form of address used for certain peers and, in some cases, their family members.

The system gets stranger. An earl’s wife is a countess, but he is not called a count. A duke is a peer, but you normally address him as “Duke,” not “Lord.” And a baron, despite being the lowest-ranking peer, is generally called “Lord.”

Many hereditary titles still pass from one generation to the next according to centuries-old inheritance rules. But inheriting a title does not necessarily mean inheriting the ancestral mansion, the land or the family fortune. Those may be owned, sold or inherited separately.

And the title no longer guarantees a place in government. Most hereditary peers lost their automatic right to sit in the House of Lords in 1999.

The titles survived. The privileges attached to them have changed considerably.