forty

adj. being 40 in number

n. number 40

40 (forty) is the natural number following 39 and preceding 41. Despite being related to the word "four" (4), 40 is spelled as "forty", not "fourty". The letters of the word "forty" are in alphabetical order; this is the only number that has this linguistic property in English.
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Noun
1. the cardinal number that is the product of ten and four
(synonym) 40, XL
(hypernym) large integer
Adjective
1. being ten more than thirty
(synonym) 40, xl, twoscore
(similar) cardinal

(n.)
The sum of four tens; forty units or objects.
  

(n.)
A symbol expressing forty units; as, 40, or xl.
  

(a.)
Four times ten; thirty-nine and one more.
  

n. adj.
چاليس, چہل