In English, we have nouns with identical singular and plural. For example,
grass, cloth, milk, rice, honey.
As I recall what I learnt many years ago in school, these are known as
non-countable nouns.
We see similar grammatical treatment in Pali. For example, odana
(rice) is always in the singular. However, there seems to be
exceptions, for example, I have seen 'ti.naani', the plural for ti.na
(grass), and 'sakkharaayo', the plural for sakkharaa (gravel).
How did the ancient Pali/Sanskrit grammatists treat such words? Thank you.