Have a field day意思

"Have a field day" is an English idiom that means to have a lot of fun, to enjoy oneself thoroughly, or to have a great time. The phrase suggests that someone is having such a good time that it's like a day spent in a field, which is often associated with leisure, relaxation, and enjoyment.

Here's an example of how you might use this idiom in a sentence:

"The kids had a field day at the park, running around and playing all afternoon."

In this context, "having a field day" implies that the children were having a lot of fun and enjoying their time in the park.