invitation
A request asking someone to come to an event or activity.
An invitation is a request asking someone to join you for an event or activity. When you receive an invitation to a friend's birthday party, they're asking you to come celebrate with them. Invitations can be formal, like a printed card for a wedding, or casual, like a text message asking if you want to come over after school.
An invitation informs someone about an event while also making them feel wanted and welcome. When you extend an invitation to someone, you're showing that you value their presence and want them to be part of something.
Invitations can be written or spoken. A coach might invite talented players to try out for a select team. A teacher might invite students to join an after-school club. Sometimes opportunities feel like invitations: when you open a new book, it's like an invitation to explore another world.
The act of inviting someone is called inviting, and the word can also describe something that looks appealing or welcoming. A cozy reading nook looks inviting on a rainy day. A difficult challenge might not seem inviting at first, but accepting it could lead to growth and accomplishment.