die Feier
celebration
A social event held to mark a special occasion, e.g. a birthday or an anniversary.
Wir organisieren eine kleine Feier zum Abschluss des Projekts.
We are organizing a small celebration to mark the completion of the project.

celebration
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celebration
A social event held to mark a special occasion, e.g. a birthday or an anniversary.
Wir organisieren eine kleine Feier zum Abschluss des Projekts.
We are organizing a small celebration to mark the completion of the project.

The noun 'die Feier' (the celebration) is derived directly from the verb 'feiern' (to celebrate). When you celebrate something, you hold a celebration.
Wir feiern seinen Geburtstag mit einer großen Party.
We are celebrating his birthday with a big party.
'Feier' is often the second part of a compound noun that names the occasion for the celebration. Examples include 'Geburtstagsfeier' (birthday party), 'Hochzeitsfeier' (wedding celebration), 'Weihnachtsfeier' (Christmas party), or 'Abschlussfeier' (graduation/end-of-program celebration).
Bist du zu Annas Abschlussfeier eingeladen?
Are you invited to Anna's graduation party?
To indicate the occasion or reason for a celebration, the preposition 'zu' (+ dative) is often used. For example, 'eine Feier zu Ehren von jemandem' (a celebration in someone's honor) or 'eine Feier zum Jubiläum' (a celebration for the anniversary).
Die Firma gibt eine Feier zum 20-jährigen Bestehen.
The company is holding a celebration for its 20th anniversary.
Adjectives help you understand the type of celebration. Words like 'privat' (private) or 'klein' (small) point to an informal party. Adjectives like 'offiziell' (official), 'öffentlich' (public), or 'feierlich' (ceremonial/festive) indicate a formal ceremony.
Wir machen nur eine kleine Feier im Familienkreis.
We're only having a small celebration with family.
Common verbs used with 'Feier' in the meaning of 'party' are 'eine Feier geben' (to hold a celebration), 'eine Feier schmeißen' (to throw a party, colloquial), 'eine Feier organisieren' (to organize a celebration), or 'zu einer Feier einladen' (to invite someone to a celebration).
Meine Nachbarn haben mich zu ihrer Gartenfeier eingeladen.
My neighbors invited me to their garden party.
evening
'der Abend' and 'die Feier' can both mean an event. 'der Abend' mainly says that the event takes place in the evening, for example 'ein Musikabend' (a musical evening) or 'ein Elternabend' (a parents' evening). 'die Feier' emphasizes the occasion and the celebrating, such as a birthday, an anniversary, or a ceremony. They can be confused because a celebration often takes place in the evening. If the time is important, 'Abend' fits; if the special occasion is important, 'Feier' fits.

Die Feier zum Geburtstag meiner Freundin dauerte bis Mitternacht.
The celebration for my friend's birthday lasted until midnight.
Morgen ist ein Infoabend, bei dem mein Kollege den neuen Plan erklärt.
Tomorrow there is an information evening where my colleague will explain the new plan.