水底

shuǐdǐ
the bottom of a body of water

CEDICT

bottom or bed of a body of water

Wiktionary

Entry Composition

1 水 shuǐ
  1. water
  2. (after a name) ... River
  3. to swim (used mostly in 会水 huìshuǐ and 水性 shuǐxìng)
  4. (coll.) lacking in substance; shoddy
  5. (bound form) additional cost; extra income
  6. classifier for washings of a garment
2 底 dǐ
  1. bottom; base
  2. background; foundation
  3. copy (of a manuscript or receipt etc) kept as a record
  4. (suffix) end of a year or month
  5. (math.) radix; base (abbr. for 底数 dǐshù)

Containing this entry

水底相机 shuǐdǐxiàngjī underwater camera
水底捞针 shuǐdǐlāozhēn