spine / backbone

(colloquial) a girlfriend (a female partner in a romantic relationship)

captive, prisoner of war

exempt

old documents / (in palaeography) historical documents written to convey a specific intention between a sender and receiver; generally inclusive of written material through the mid-19th century

a queen regnant

(historical) a Japanese prince's unmarried daughter who is descended from the reigning emperor through no more than five generations ("princes" include 親王 (shinnō) or 王 (ō))

giving a letter to the government, lord or noble to express one's opinion; or the letter of them

modesty

modest