triumphal
Describing a grand celebration or display of great victory.
Triumphal describes something related to a great victory or success, often celebrated publicly and proudly. When an athlete returns home after winning an Olympic gold medal, their hometown might organize a triumphal parade with cheering crowds lining the streets. Ancient Roman generals who won major battles rode through Rome in triumphal processions, celebrating their conquests with the entire city watching.
The word carries a feeling of grand, joyful celebration after achieving something difficult. A scientist might make a triumphal announcement after years of failed experiments finally lead to a breakthrough. When a basketball team wins the championship, their triumphal march back to the locker room shows their pride and joy.
Triumphal is closely related to triumphant, but there's a subtle difference: triumphant describes the feeling of victory (a triumphant smile), while triumphal describes the celebration or ceremony that honors that victory (a triumphal arch). Many cities have triumphal arches, grand monuments built to commemorate military victories or other great achievements. The Arc de Triomphe in Paris is one famous example, built to honor French military successes.