Fine. You’re a non-cheese-eating non-surrendering non-monkey.
Guilty of all three charges here.
Well honestly, it’s almost two syllables, with a triphthong.
You pronounce “fire” “foy-ay”? 
Two syllables - sigh-yah, rhymes with fye-yah. We don’t waste our precious R’s on it. We’re very sparing in their use.
I use mine all the time. In fact, I’m sitting on it right now.
I’m British and I think I need one and a half syllables to do it justice. It’s not the definite si-yer of fi-yer but it’s not just one either.
I think that’s a pretty good alternate definition of a dipthong.
Diphthong
Yep. My dad’s accent made these words all sound alike: tire, tar, tower.
In formal poetry, where beats or syllables matter, words like “sire” have one syllable or two depending on need. Handy words, those. 
Exactly! Waste it on words and you’ll have no place to sit.
This. Diphthongs have two vowel sounds, but count as only one syllable. This comes up more often in singing than speaking.
I would have said either “two syllables, of which the first one is a diphthong”, or “one syllable, which is a triphthong” (“phi” is a diphthong).
Two syllables
Syllables are rather arbitrary in English diphthongs. How many syllables does “house” have? By convention, English dictionaries treat it as one, and “household” with two.
The difficulty arises when asked if “aisle” and “taiga” have the same number of syllables. Or “fire” and “fryer”.
Additionally, English convention does not regard “R” as a vowel, even though “fire” is pronounced the same as “fighter”, with the same number of syllables, except that a /t/ is placed between the two syllables /fi/ and /er/.
The principle reason English dictionaries even address syllables, is because of the rule that printers can separate a word with a hyphen at the end of the line only where there is a syllable break, so dictionaries have to show where that is. A printer cannot separate “fi-re” with a line break, but the can “fight-er”. For no reason other than a desire to codify life with rules and pedantically yell at people who break them.
Let’s turn to an authoritative source, the OED.
According to that venerable dictionary the Brits pronounce fire as one syllable, the Americans use both one and two syllable pronunciations, presumably according to region.
Yeah…but most of those words have two syllables too.
Not me - but it’s more like “foy err”, which is how most of us pronounce foyer.
Filet steak is also pronounced “fill ett” steak One does not “fill ay” a fish.
Q: Why were the three Wise Men carrying axes and hoses?
A: Because they came from afar.
Sorry, just seemed germane.
mmm
Read that again, if you will. 
Prophetic, even.