If someone or something is rowdyish, they are a little bit noisy and rough, but not too much.
Rowdyish can make people think of fun and energy, but also a little bit of trouble.
Examples:
The kids were being rowdyish at the party.
The dog's rowdyish behavior was getting out of hand.
The rowdyish group of friends were having a good time at the park.
The rowdyish cat knocked over the vase.
The rowdyish crowd made a lot of noise at the concert.
The rowdyish puppy was running around the yard.