Double entendres have a rich history in Japanese entertainment (such as in kakekotoba)[1] due to the language's large number of homographs (different meanings for a given spelling) and homophones (different meanings for a given pronunciation).
[1] Goroawase (語呂合わせ, "phonetic matching") is an especially common form of Japanese wordplay, wherein homophonous words are associated with a given series of letters, numbers or symbols, in order to associate a new meaning with that series.
Furthermore, variants of readings may be produced through abbreviation (i.e. rendering ichi as i), consonant voicing (i.e sa as za; see Dakuten and handakuten), gemination (i.e. roku as rokku; see sokuon), vowel lengthening (i.e. ni as nii; see chōonpu), or the insertion of the nasal mora n (ん).
Like puns in English, dajare may be considered dad jokes (親父ギャグ, oyaji gyagu).
Dajare commonly involve the usage of two homophonous phrases alongside each other in a sentence, though double entendres are used as well.