“eidledum”是什么意思呀？

是小学三年级课本中的一首英语歌词。
Hop, brown squirrel, eidledum.
Hop, brown squirrel, eidledum, dee!
Hop, brown squirrel, eidledum.
Hop, brown squirrel, eidledum, dee!

这里的 eidledum, eidledum, dee! 是什么意呀？词典都查不到的。编写者也太变态了吧？这小学生才学英语，却给弄了两个词典查不到的词，那不是故意打击初学者吗？难道就没有更好的歌可替代了？

这首歌词怎么翻译呀？
可不要只解说是“一种不孩玩的游戏”，那太不好懂了。是一种什么游戏？

一种小孩子用来玩的游戏，
用其他词替换eidledum，以
提示其他小孩移动。说白了
，这就是一个占位符。

17. hop old squirrelcd 1:18directions: begin by having children hop freely to the beat as they sing the song. ask the children how else the squirrel might move. repeat the song changing the action to what the children suggest.eg. run old squirrel, crawl old squirrel, fly old squirrel etc. try substituting the word ‘listen’ for ‘eidledum’. on the word ‘listen’ have the children freeze until you signal them to move. you will enhance their listening skills in all subject areas, using this variant of the game.teaching purpose/suggestions: moving to the beat, creating new movements, prepare mi-re-doplay the game song #17 “hop old squirrel”. if you substitute the words “listen - listen” for “eidledum”, this simple game becomes an excellent watching and listening exercise.hop old squirrel uses the solfa notes mi re and do. in grade 2, review the song, and use it to label the notes mi, re and do. 一种小孩子用来玩的游戏，用其他词替换eidledum，以提示其他小孩移动。说白了，这就是一个占位符。 以上是这个游戏的玩法。