A fizzle is when a fun activity or situation slowly loses its excitement and becomes boring. You know how sometimes you're really looking forward to something, but when it finally happens, it doesn't live up to your expectations? That's what a fizzle feels like.
When we say that an event "fizzled out", we mean that the energy and enthusiasm that was supposed to be there just wasn't. It might have started strong, with lots of people excited and looking forward to it, but as time went on, things began to slow down and eventually became dull. This can happen with parties, concerts, or even new hobbies - anything that we thought would be super fun, but ends up being kind of a letdown.
To sputter or hiss.
Example: The soda fizzled for several minutes after it was poured.
