noun

Idiomatic expression, jocular, humorous term.
  1. useless book learning, knowing the theory but not being able to put it into practice, swim practice on a tatami mat.

Variations

Pronunciation Kanji Kana Is Common
畳水練 たたみすいれん

Contained Kanji Breakdown

tatami mat, counter for tatami mats, fold
たた.む たたみ ジョウ (Early Jr. High, N2)
rice field, rice paddy
た デン たん (1st, N4)
suitable, right, fitting
ギ よろ.しい
wa-shaped crown radical (no. 14)
ベキ (Kentei 1)
moreover, also, furthermore
か.つ ショ ソ (Early High School, N1)
month, moon
つき ゲツ ガツ (1st, N5)
one, one radical (no.1)
イチ いっ ひと- (1st, N5)
water
みず スイ み (1st, N5)
practice, gloss, train
レン ね.る ねり (3rd, N2)
thread
いと シ (1st, N2)
short thread radical (no. 52)
ヨウ ちいさい (Kentei 1)
little, small
ショウ こ- ちい.さい (1st, N5)
feathered stick, barb radical (no. 6)
ケツ かぎ (Kentei 1)
eight, eight radical (no. 12)
ハチ や はっ (1st, N5)
east
トウ ひがし しの (2nd, N5)
tree, wood
き モク こ- (1st, N5)
day, sun, Japan
ひ にっ ニチ (1st, N5)