Joanna and Chris are expecting a boy soon -- a little brother for Joanna's sons Isaac James and Oscar Joseph, and Chris' son Joshua George.
They are looking for "an unusual name that suits the other boys' names." The middle name will be Brian after Joanna's father.
Joanne's List:
Rufus
Raphael - Chris dislikes as he feels its incongruous when they have no foreign links.
Rex
Felix
Barnabas
Sebastian
Theo
Chris's List:
Rufus
Otto - Joanne feels it is too close to Oscar and would prefer not to repeat letters.
They both love Rufus, but are looking for extra inspiration.
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Chalk me up as another vote for Rufus! I love that it shares the same (subtle) 's' sound that all the other boys' names have, has a dapper literary vibe, and is well known enough to not be confusing, but sits outside of the top 200 in popularity.
The rest of your list is just as fabulous. Felix and Rex in particular strike me as sharing much of Rufus's urbane and stylish qualities.
Suggestions:
Lucas – Like Rufus, Lucas has a smart and urbane style, echoing the subtle 's' sound in Oscar, Joshua and Isaac. It's ancient routes tie it in nicely with biblical Joshua and Isaac and Gaelic Oscar.
Silas – Edgy-yet-refined but seriously underused. For me Silas perfectly ticks the box of being unusual yet suiting your current sibset with its sleek style.
Bertram – An old Germanic name with a strong meaning of "bright raven." It's a known name which is very underused -- making it ripe for the picking.
Rupert – Rupert and Rufus are linked in my mind for similar style: shabby aristocrat meets medieval knight. It's friendly and serious at the same time.
Fraser – While Joshua and Isaac share Hebrew routes, urbane Fraser matches Oscar's Gaelic heritage.
Maxwell – Another smart Gaelic surname that's friendly, accessible, yet still below the top 100. Even less common is literary Maxim or Welsh Macsen.
Xavier – Polished Xavier has that oh-so-fashional X and sits in the "unusual but not weird" boundary.
Alban – With ancient Celtic routes, Alban is the name of Britain's first native saint and a name connected with solstice. It's unusual but not weird with its fashionable two-sllable -n ending.
Virgil – A famous classical poet and a (recently revived) Thunderbird! Virgil is undeniably cool and extremely rare.
August / Augustine – Thanks to St Augustine of Canterbury, Augustine was a popular name in the Middle Ages and still retains its knightly polish. August is a short form which also works as a standalone virtue-name.
Malachi / Malachy – Malachi (MAL-a-kī) is a quirky biblical name while Malachy (MAL-a-kee) is Irish, echoing Oscar's routes. Both are worth considering.
Elias – Another name sitting in the sweet spot between #100-300 is this sleek Greek form of strong biblical favourite Elijah.
Fergus – Capable Fergus shares Oscar's affable Gaelic charm and also has that subtle 's' sound.
Duncan – Literary and rugged Duncan is very much underused yet recognisable and longstanding.
Lachlan – Uncommon, unusual and high accessible. Lachlan feels very contemporary but has bags of history.
Blaise – Saintly Blaise has both Latin and Old English routes and medieval repute. Not even in the top 1000, Blaise is a modern-sounding, underused gem. In a similar vein is another saintly name Blane (also found as Blaine) and literary Blake.
Wild Card: Falco – A Roman name meaning "falcon" which was used in this country from the Roman Britain to the Middle Ages. It has since become a rarity, but with that stylish 'o' ending, it sits nicely with the likes of fashionable Theo, Hugo, Rocco, Milo and Arlo.
Best of luck deciding on the perfect name. Please keep us updated!