Are there words in Mandarin written by characters for other words that mean the same thing? For example, in written Chinese 给 is used a ideograph for "to give" and is read with whatever the word for "to give" is in the various languages, even if the word is not cognate or in any way related to the etymology of 给. Are there words in Mandarin that are written with characters for words that are not etymologically related? 

If it's just selecting a phonetic loan for a word that has never been written before, that is understandable because you have to start somewhere. I'm more curious about stuff where the pronunciation/etymology is completely unrelated but a character is used just because of its meaning.
A good example is numbers in Chinese.

https://en.wikipedia.org/wiki/Chinese_numerals#Standard_numbers