Hostile Offer
Artist formerly known as Eagle Peninsula
I don't see a good argument to say that Money isn't a defining Floyd song considering that it's the song that got them big in the states, is their biggest hit on their most successful album by a long shot, and is an incredibly creative piece of music. Money is the reason why they went from big to superstar big and one of the best of all time. They followed it up with some great pieces of music and even if those songs can be argued as most popular, Money is their biggest claim to fame and success.
I guess that's you then, Money is not generally a song I associate with when talking about defining Floyd songs. Dark Side was the album that got them into fame but they followed it up with opuses that IMO overshadow it in musical creativity, but again I guess that's just me and even on Dark Side, I would consider Time as a more iconic Floyd piece than Money. Don't get me wrong though, Money is still a great song.