The Different Meanings Of The Coloured Shag Bands Can Someone Please List The Different Meanings Of The Word Rationalize For Me?

Can someone please list the different meanings of the word rationalize for me? - the different meanings of the coloured shag bands

I saw that meaning in the dictionary, but I do not understand the meaning. I have a problem with reading comprehension, so that I would be really grateful if someone could use the list of the different meanings of this word for me. And also very useful if you are getting the word in a sentence for me, help me to better understand their significance.