Here are the possible solutions for brief cause for celebration and this puzzle's title clue
Answer
Clue
Relevancy
bday
Clue
Brief cause for celebration, and this puzzle's title
Brief cause for celebration
tmi
Clue
Brief version of this puzzle's title hidden in eight long puzzle answers
eve
Clue
Celebration before the celebration?
Definition
a poetic word for evening, also EEVEN, EEVN, EEVNING
valueofpi
Clue
Subject of an annual March 14 celebration and of this puzzle, celebrated in both a literal and a numerical way in the first square of the starred answers, reading left to right
meta
Clue
Puzzle-within-a-puzzle puzzle
Definition
(US) concerned with cultural conventions; (of an artistic work) self-referential
