As stated in the title. I aware that some languages have some remnants of dual grammtical numbers.
There are also languages that have more than singular, dual, plural. A good overview is provided by Corbett 2000, which is an really good overview over the category of Number in general. Here are some examples he gives (§ 2.2):
- Languages with the trial (for “three”): Larike (Central Moluccan), Ngan’gityemerri (Daly), Marrithiyel (Daly), Anindilyakwa (the language of Groote Eyland)
- Languages with paucal (for “small numbers”): Bayso, Yimas, Boumaa Fijian, Paamese, Manam, Ambrym
It is a controversial question if there is a true quadral (for “four) -- and some languages also have special encoding for “large numbers” though there is a lot of variation going on. The wikipedia article on grammatical number is also quite good.
Corbett, Greville G. 2000. Number. Cambridge: Cambridge University Press.
For a language with a large speaker base, Arabic has the dual. You can easily find more examples here: