Meaning of 'TWEEN in English
/tween/ , prep.
1. contraction of between.
2. Also, tween, tweeny . a youngster between 10 and 12 years of age, considered too old to be a child and too young to be a teenager.
[ 1250-1300; ME twene, aph. var. of atwene (see A- 1 ) or betwene BETWEEN ]
Random House Webster's Unabridged English dictionary. Полный английский словарь Вебстер - Random House . 2012