Many languages have words expressing indefinite and fictitious numbers—inexact terms of indefinite size, used for comic effect, for exaggeration, as placeholder names, or when precision is unnecessary or undesirable. One technical term for such words is "non-numerical vague quantifier". Such words designed to indicate large quantities can be called "indefinite hyperbolic numerals".
Specific values used as indefinite
In English, some words that have a precise numerical definition are often used indefinitely: couple, 2; dozen, 12; myriad, 10,000.
In Japanese,, 8000, is used: means a variety of herbs and means eternity.
The number 10,000 is used to express an even larger approximate number, as in Hebrew revâvâh, rendered into Greek as μυριάδες, and to English myriad. Similar usage is found in the East Asian or , and the South Asianlakh.
In Irish, 100,000 is used, as in the phrase, "a hundred thousand welcomes" or Gabriel Rosenstock's poetic phrase mo chéad míle grá.
In Welsh, cant a mil, literally "a hundred and thousand", is used to mean a large number in a similar way to English "a hundred and one". It is used in phrases such as cant a mil o bethau i'w wneud "a hundred and one things to do" i.e. "many, many things to do".
In Swedish, label=none is used, meaning "fifty-eleven".
In Thai, ร้อยแปด , means both 108, and miscellaneous, various, plentiful.
Other specific numbers are occasionally used as indefinite as well. English does this with count nouns that refer to numbers: a dozen/dozens, a score/scores, a hundred/hundreds, and similarly thousand, million, billion. Unlike cardinal numbers, these can be pluralized, in which case they require of before the noun, and require the indefinite article "a" in the singular but one million letters'' ).
Umpteen
Umpteen, umteen or umpty is an unspecified but large number, used in a humorous fashion or to imply that it is not worth the effort to pin down the actual figure. Despite the -teen ending, which would seem to indicate that it lies between 12 and 20, umpteen can be much larger. "Umpty" is first attested in 1905, in the expression "umpty-seven", implying that it is a multiple of ten. Ump came from a verbalization of a dash in Morse code. "Umpteen", adding the ending -teen, as in "thirteen", is first attested in 1918, and has become by far the most common form. In Norwegian, ørten is used in a similar way, playing on the numbers from tretten to nitten, but often signifying a much larger number.
-illion
Words with the suffix-illion are often used as informal names for unspecified large numbers by analogy to names of large numbers such as million, billion and trillion. These words are intended to denote a number that is large enough to be unfathomable and are typically used as hyperbole or for comic effect. They have no precise value or order. They form ordinals and fractions with the usual suffix -th, e.g. "I asked her for the jillionth time", or "-illionaire" to describe a wealthy person.
Sagan's number
Sagan's number is the number of stars in the observable universe. It is named in honor of Carl Sagan. This number is reasonably well defined, because it is known what stars are and what the observable universe is, but its value is highly uncertain.
In 2010, it was estimated to be 300 sextillion. This would equal the number of H2 molecules in 1 gram of hydrogen.
Sagan's number is to be distinguished from the sagan unit or the humorous use of the term "sagan" to denote any large quantity—specifically, any number of at least four billion, due to Sagan's association with the phrase "billions and billions".
