Is this your crossword clue?
"submerged" is also used as a crossword clue. If that's what you saw, the answer is often underwater (10 letters).
Definitions
growing or remaining under water
Used in a sentence
“Near-synonym: submarine (sometimes synonymous)”
“Janet was completely submerged when she was snorkeling.”
Source: Wiktionary, CC BY-SA 4.0
Used as a crossword answer2 curated clues
01“Below liquid surface”9 letters
02“Underwater”9 letters
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