Caligula ( ), properly Gaius Julius Caesar Augustus Germanicus (31 August AD 12 – 24 January AD 41) was Roman emperor from AD 37–41.
 Born Gaius Julius Caesar Germanicus (not to be confused with Julius Caesar), Caligula was a member of the house of rulers conventionally known as the Julio-Claudian dynasty.
 Caligula's biological father was Germanicus, and he was the great-nephew and adopted son of Emperor Tiberius.
 The young Gaius earned the nickname "Caligula" (meaning "little soldier's boot", the diminutive form of "caliga", hob-nailed military boot) from his father's soldiers while accompanying him during his campaigns in Germania.
Carr is a common surname in northern England, deriving from the Old Norse "kjarr ", meaning a swamp.
 Kerr is a Scottish variant, often from the Norse and (particularly on the west coast and Arran) from the Gaelic "ciar ", meaning "dusky".
 Carr is also a common surname in Ireland, where it often derives from the nickname, "gearr ", meaning "short of height".
 In some cases it is thought to come from the Welsh word "cawr ", meaning giant.
Mayor is an English and Spanish-language surname with several etymological origins.
 The English-language name is sometimes a variant spelling of "Mayer", and thus derived from the Middle English and Old French "mair", "maire" (in turn derived from the Latin "maior", meaning "greater", "superior"); this surname originated from the title of a mayor.
 The surname "Mayor" can also be derived from a nickname, derived from the Spanish "mayor", meaning "older", borne by the elder of two individuals with the same name.
 Another origin of the surname is from an occupational name, derived from the Spanish "major", meaning "governor", "chief".
 The surname can also be a Catalan variant of the surname "Major", derived from "major", meaning "greater", used to denote an elder son of a particular family or an important person.
 The surname "Mayor" can also be derived from the Yiddish personal name "Meyer", which is derived from the Hebrew language  "Meir", which in turn means "enlightener".
Koninklijke Sint-Truidense Voetbalvereniging (] ), commonly known as Sint-Truiden or STVV (] ) or by their nickname De Kanaries (] , is a Belgian professional football club located in the city of Sint-Truiden in Limburg.
 Sint-Truiden plays in the Belgian Pro League.
 Their best ranking was a second place in 1965–66.
 They also reached the final of the Belgian Cup twice.
 The club was founded in 1924.
 They are matricule number 373.
 The club colours are yellow and blue, hence their nickname "De Kanaries", meaning 'The Canaries'.
 They play their home games at the Stayen since 1927.
Valeria Messalina, sometimes spelled Messallina, (c. 17/20–48) was the wife of the Roman Emperor Claudius.
 She was a paternal cousin of the Emperor Nero, a second-cousin of the Emperor Caligula, and a great-grandniece of the Emperor Augustus.
 A powerful and influential woman with a reputation for promiscuity, she allegedly conspired against her husband and was executed on the discovery of the plot.
 Her notorious reputation arguably results from political bias, but works of art and literature have perpetuated it into modern times.
Baran is a rare surname from various origins.
 It is supposed to be another variant of Baron.
 In Gaelic the meaning of the name Baran is: Noble warrior.
 In Russian the meaning of the name Baran is: The ram; forceful; virile.
 In Teutonic the meaning of the name Baran is: Noble fighter.
 In Persian, Kurdish and Turkish baran means rain is a loan word from Persian.
 In older Bhojpuri dialect it is misspelling of Varan, or Sanskrit Varna.
 In India it is not used as a surname but is/was sometimes found among descendants of indentured labourers from Bihar or Eastern UP as a misspelt form of Varna, especially in compound given names like Rambaran meaning "having the qualities of the clan of Lord Rama".
 It is rarely found in Mexico as a variant of Vara, from Portuguese and Spanish: from vara ‘rod’, ‘stick’, ‘yardstick’ (Late Latin vara ‘forked stick’), applied as a nickname or metonymic occupational name in any of various possible senses; it may have been given to a keeper of animals, who used a stick to urge his charges on, or to an official who was responsible for checking weights and measures or who carried a rod as a symbol of his office.
The surnames McCabe and MacCabe are Scottish and Irish surnames.
 They are Anglicisations of the Gaelic Mac Cába, a patronymic name meaning "son of "Cába"".
 The nickname or personal name "Cába" is of uncertain origin.
 The surname can be written in modern Scottish Gaelic as MacCàba and MacCaibe.
 Patrick Woulfe considered that the surname was possibly derived from a nickname, meaning "a cap", or "hood".
 Henry Harrison suggested the name was from the Gaelic "Mac Aba", meaning "son of the Abbot".
 If Harrison is to be believed then the surname would have a similar etymology as the surnames "MacNab", "McNab", which are from the Gaelic "Mac an Aba", "Mac an Abadh".
Karaklajić () is a Serbian surname, derived from the Turkish adjective "kara", meaning "black", and the nickname "Klaja" from the Serbo-Croatian word "kljast", meaning "crippled".
 The surname was historically found in the Sokol "nahija" villages of Zaovine, Rastište, Perućac and Brasina.
 The Zaovine Karaklajići migrated from Bijelo Polje, and earlier from Kuči; the Rastište Karaklajići were from Zaovine.
 It is today found in Šarenik as well.
 It is related to the surname Karaklaja, which was derived directly from the nickname; hajduk Ivo Matović from Ivanjica used it (1868), though it was found earlier as a surname in the village of Majdan (1825) and in Užice (1866)
The surname Dunn has several different origins.
 In some cases it is an Anglicised form of the Irish surname "Ó Duinn", meaning "grandson of "Donn""; the Gaelic "Donn" was originally a byname, meaning "brown-haired" or "chieftain".
 Another origin of the surname "Dunn" is from the Middle English "dunn", meaning "dark-coloured"; this name originated as a nickname for one with dark hair or skin.
 Another origin is from a habitative name, derived from Dun in Angus, Scotland; this place name is derived from the Scottish Gaelic "dùn", meaning "fort".
 Another origin is from the Gaelic "donn", meaning "brown".
McKinley is a Scottish and Irish surname historically associated with northwestern Ireland's County Donegal, and the over-kingdom of Ulaid in northeastern Ireland and the Scottish Highlands.
 The McKinley are of the ancient Ulaid race and are a branch of its "Red Branch" MacDunleavy (dynasty) royal house of the Dal Fiatach which dominated the kingship of the over-kingdom of Ulaid (original Gaelic language Mac Duinnshléibhe).
 Entomology for the origins of the surname proposes that the Anglicized surname McKinley, like the surname MacNulty (Gaelic Mac an Ultaigh, trans.
 "son of the ultonian, ulidian or ulsterman", arose originally from a Gaelic nickname given the deposed MacDunleavy dynasty royals while exiled in Tirconnell and elsewhere.
 Being, also, one of Ireland's ancient hereditary medical families, the MacDunleavy (variant English spelling MacDonlevy) were in Tirconnell accorded the high Gaelic status of "ollahm leighis" or the official physicians to the O'Donnell clan in County Donegal and practiced as physicians while exiled in Argyll, Scotland.
 The nickname was Mac an Leigh.
 Per this scenario the Gaelic language patronymic forming prefix "Mac" (meaning "descended of") is joined to the Gaelic language "Léigh" meaning leech, but denoting a physician.
 Leeching (medical) having been for millennia, in Gaelic Ireland and elsewhere, a commonly employed medical practice.

Question: What is the meaning of the nickname of Messalina's second-cousin?
Answer: "little soldier's boot"