What's that word - meaning "unanimous" or "of one mind", in mono- form?

I can’t think of a mono- word, but how about homogeneous?

Monophonic? Being of one voice.
Check this out if that not it.

can’t find mono- variant but what about UNI-form, or [a short list]:
concordant, concurrent, concurring, congruent, congruous, consentaneous, consentient, uncontested, uncontradicted, uncontroverted,unisonant, unisonous, unopposed

@everephebe mon·o·phon·ic/ˌmänəˈfänik/Adjective
1. Consisting of a single musical line, without accompaniment.
2. (of sound reproduction) Using only one channel of transmission.

@everephebe I think that relates specifically to sound, not thought.

Monolithic comes close when used metaphorically.

I was thinking of monolithic too. Metaphorically, it means presenting a solid, uniform front, like a huge block of stone.

I wouldn’t use that in your sentence, though. Try one of these.

@gailcalled: Merci, fellow lecteur.

@Jeruba: Mon semblable, ma soeur.

I don’t think there is one, for of one mind or of one thought. It would have to be homoment, or homologue and that’s already taken, or homophrene or something like that.

Edit. I think I found one: homothymadon. That is apparently the Greek for ‘of one thought, of one mind” Is that what you were thinking? I’m thinking no. ;-0

Psych is the root for mind in greek, which is where mono comes from. Monopsych, doesn’t work does it? When I mentioned monophonic I thought it was a long shot, but the phono root φωνή, phōnē, “sound, voice” doesn’t just mean sound, it also has the meaning of voice. Which is why I suggested it.

I think that @Allie is on the right track with thinking it’s a homo root, for example: homophrón means “of one mind.”

Homothymadon has a similar meaning: with one mind, with one accord, with one passion.
Also homophrosýnē, like-mindedness.

One person only has one mind and is of one mind, literally…so if there was a word, wouldn’t it be redundant?

@ladymia69 No, because we’re talking about a society – that they didn’t agree on the subject nearly as much as is commonly portrayed today.

Also, have you not read/seen/heard Batman? Two-Face was always of “two minds” because he had conflicting views on everything.

Monotheistic?

Monomaniacal. It means obsessed on one thing, but it also means “Intent concentration on or exaggerated enthusiasm for a single subject or idea.”

How about monopsychologomentiunignosicaptiphrenic? I could have thrown a few more roots, suffixes and prefixes in there but it would have made the word awkward and cumbersome.

Monocultural? ( Hive Mentality, Hive Mind )

Look at the sample sentence. It’s in the original question. Supposedly the term of choice will make sense in it.

@MyNewtBoobs, I know this is an entertaining exercise, but why not forget the mystery word and just say The views on taxation in America during the 2000s were diverse. ?

@Jeruba I actually ended up going with @Allie‘s suggestion for this paper. But I heard this word just today, and I can’t remember it now, so this is totally different; it’s of the “Omg, I have to know!!” variety ;)

Monochromatic? boom!

Monadic? (All of one piece)
Monochiral? (Having only one side / orientation)
Monideal? (Recognizing only one thought)
I made up the latter two.

I bet Mon Cul would know.

MONOMORPHIC ( Monomorphism/ Monomorphous )

I think @Afos22 came the closest – a monochromatic viewpoint would be all one color, thus all the same.

The rest don’t really convey agreement of opinion.

I looked up “of one mind” in a thesaurus, and six entries came up ,none of which had a synonym starting with “mono-”.