Sawney — Scottish lowlands variant of "Sandy" short for the masculine name "Alexander". Here, presumably, a shortened version of "Alexandria", though this usage is nowhere reported. The OED gives three further meanings: 1. derisive nickname for a Scotchman; 2. a simpleton, fool; 3. slang bacon.

Father Taylor/O'Táighléir — his name, presumably, is Edmund Taylor. This he has "Gaelicized" to Éamonn O'Táighléir (roughly pronounced "toy-lair" – the "gh" sound is fairly silent in IE). The Irish for "tailor" is actually táilliuir (pron. "toy-lure"), not táighléir – but the latter has the advantage of "looking" more Gaelic. Even accepting Táighléir, the O-apostrophe before it is mishandled: the Gaelic name would be written "Ó Táighléir" (the O-apostrophe is an English-language convention).

Eveline hears it as "Amen O'Toiler" and describes it as "a sermon in itself" (Ch1.3). Doyler dismisses it as "cod-Irish" (Ch4.2).

cf Irish Ireland.

The same strong voice more near
Said cordially, My Friend, what cheer?
— Wordsworth, The Waggoner.
What cheer polka
"What Cheer polka" by J.H. Collins, 1874.
what cheerPartridge calls it a "colloquial greeting" of the "lower classes", and dates it C.18-20. OED gives its meaning as "what is your state or mood?" "how are you?" By late 19th century it had descended to the Cockney "wotcher" (Routledge Slang), and later still to the Harry-Potteresque "wotcha". It is Doyler's familiar greeting: the first words he addresses to Jim (Ch 2.3 < ) and the last (Ch 21.2). Indeed, it forms the last line of the novel. Jim finds the usage "quaint" (Ch 3.1). It seems Doyler has learnt it from his father (or step-father): Mr Doyle greets Mr Mack (Ch 1.1 < ) with "what cheer to see you so spry". In the same section, Mr Doyle calls Mr Mack "pal o' me heart" – another of Doyler's familiar terms.

Doyler — familiar nickname in Ireland of a male surnamed Doyle.

The surname Doyle derives from the Irish Dubh Gall meaning "dark stranger" or "dark foreigner". It was the name the native Gaels gave to the 9th century Viking raiders from Denmark. (Those from Norway were called Fionn Ghaill – "fair-haired foreigners".) These Vikings eventually founded Dublin; their descendants, now assimilated as the clan O'Doyle, settled the eastern Leinster seaboard (counties Dublin, Wicklow and Wexford – in the sense of towns, all Viking foundations). By the 19th century, the surname was the twelfth most common in Ireland. Cognates to Doyle include the surname MacDowell and the first name Dougal.

The Urban Dictionary reports a recent slang meaning of Doyler as "great in bed".

Vergilius Romanus
Meister des Vergilius Romanus, "Shepherd with Flocks", 5th century

Virgil's Second Eclogue — "the most famous poem on male love in Latin literature" — Encyclopedia of GLBTQ.

Corydon, a "simple shepherd" usually identified with Virgil himself, burns with love for Alexis. Alexis, however, is a slave-boy and "his master's darling". Corydon imagines a life for them together, devoted to hunting and herding. "With me in the woods," he asserts, "you shall rival Pan in song". Alexis appears indifferent: Corydon's ardour turns to despair – "Alas, alas! What hope, poor fool, has been mine?" In the end, Corydon judges himself a "clown" for neglecting the homelier work of the farm for his mad passion. Yet still love burns in him – "for what bound can be set to love?"

Malliol, Corydon
Aristide Malliol, "Corydon the Shepherd", 1926
"The Second Eclogue is by far the most important Classical pastoral poem depicting love between men, and continued to inspire poets who wished to honor male friendship and love through the Middle Ages, the Renaissance, the Romantic Period, and to the present. ... The poem has been so influential on writers and other artists interested in depicting intimate relationships between men that even the names Corydon and Alexis became signifiers of male love; when André Gide published his bold, courageous defense of homosexuality shortly after the First World War, he entitled it Corydon." – Eric Patterson, On Brokeback Mountain, 2008.
P. Vergili Maronis: Ecloga Secvnda.
Virgil: Second Eclogue.