20

Year 20 was a leap year starting on Monday (link will display the full calendar) of the Julian calendar.
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Noun
1. the cardinal number that is the sum of nineteen and one
(synonym) twenty, XX
(hypernym) large integer
Adjective
1. denoting a quantity consisting of 20 items or units
(synonym) twenty, xx
(similar) cardinal

n. (Hira=にじゅう) twenty, number 20

= 20 (twenty).
Ex: The first edition was published in 20 volumes in 1950.

20