Something along the lines of 'hero of the occasion', but specifically for birthday? If there isn't, how would you otherwise say that?
('the subject of birthday party', 'the hero of this birthday party', 'birthday's hero' all sound stupid somehow).
I have often heard the person in question informally referred to as the "Birthday Boy/Girl". e.g.
The birthday girl was having a wonderful time at her party.
Though its usage isn't limited to birthday parties, I like "guest of honor."
In a birthday situation, the word 'celebrant' would be generally understood to mean the one whose birthday is being celebrated.
celebrant
is a legal term meaning one who is authorized to preside over a wedding (sometimes a clergyman or a judge but often just someone who registered with the Commonwealth to fill that role) -- not the parties being wed.
Commented
Jul 19, 2011 at 21:51
My first reaction was that the birthday boy or girl is the "Fetted" person, which upon research appears to not be a (current) dictionary word!
For what it’s word Here are some usages of it from culture, via https://www.wordnik.com/words/fetted:
In hindsight, asked Marr "is there anything different you might have done over the past decade, anything you did wrong ... maybe became too enthrawled by the magic of these bankers you knighted, fetted, appointed to high office?"
Sorry Seems to Be the Hardest Word
Living in an age when women as writers and playwrights were not as evident or plentiful as they are today, Hellman felt she could take liberties with the truth knowing full well how Hemingway and other fetted and celebrated male writers were also bound to fudge the truth, or embellish.
The scandalous Lillian Hellman
It seems to be very fringe but a fun and useful word, despite the similarity to "Fetid".
Would celebrantee be okay (although maybe a bit neologismic)?
The word celebrant may be the best, though Christians uses it in their holy masses here in Uganda.