Rhythmical
Rhythmic
な adjective
Rhythm is 律動, but by adding a 的 in there we get the adjective version of that word, making it rhythmical or rhythmic.
Note that リズミカル and テンポのいい are much more common words to use for "rhythmical" and “rhythmic” respectively, but you may sometimes see 律動的 in formal writing.
The reading is the same as 律動. The 的 part you should also be able to read by now.
この音楽はとても律動的ですね。
This music is very rhythmic.
トーフグチームの中で、一番律動的にラジオ体操をしていたのは、カナエです。
Out of the Tofugu team, Kanae was doing the radio gymnastics the most rhythmically.
今朝、たくさんの兎が庭で律動的に飛び跳ねているのを見ました。
This morning, I saw a lot of rabbits jumping rhythmically in my garden.