countless

As a determiner umpteen

is relatively large but unspecified in number.

As an adjective countless is

too many to count; innumerable or incalculable.

As an adjective countless

is too many to count; innumerable or incalculable.

As a noun abundance is

a large quantity; many .

As adjectives the difference between imponderable and countless

is that imponderable is imponderable while countless is too many to count; innumerable or incalculable.

As a noun imponderable

is imponderable, intangible.

As adjectives the difference between nameless and countless

is that nameless is not having a name; unnamed while countless is too many to count; innumerable or incalculable.

As adjectives the difference between countless and multiple

is that countless is too many to count; innumerable or incalculable while multiple is multiple.

Large is a related term of countless.

As adjectives the difference between large and countless

is that large is of considerable or relatively great size or extent while countless is too many to count; innumerable or incalculable.

As a noun large

is (music|obsolete) an old musical note, equal to two longas, four breves, or eight semibreves.

Prodigious is a related term of countless.

As adjectives the difference between prodigious and countless

is that prodigious is very big in size or quantity; gigantic; colossal; huge while countless is too many to count; innumerable or incalculable.

As adjectives the difference between countless and unnumerable

is that countless is too many to count; innumerable or incalculable while unnumerable is .

As adjectives the difference between transfinite and countless

is that transfinite is beyond finite while countless is too many to count; innumerable or incalculable.

As a noun transfinite

is a transfinite number.