"Then We threw them into the sea" [51:40], meaning: into the ocean. "While he was blameworthy" [51:40], meaning: a sinner, and his sin was polytheism (shirk).
Muhammad said: It is said: A man is 'alāma' (deserving of blame) if he commits a sin for which he is blamed.
Tafsir of Surat al-Dhariyat from verse 41 to verse 45.