young ladyship
/ˌjʌŋ ˈleɪdɪʃɪp/noun
1With possessive adjective: a title of respect given to a young lady, especially one of noble rank. Also: a woman who is addressed as ‘your young ladyship’. Compare ladyship 2c. Now chiefly archaic.
2The fact or condition of being a young lady.
Origin
Early 18th century; earliest use found in Richard Steele. From young lady + -ship, in sense 1 after ladyship.