Fetching details from the dictionary...
to make muddy (of a liquid); to make cloudy; to make turbid; to roil
to make ambiguous; to evade (e.g. the point); to be noncommittal about
答えを濁してはっきり言わなかった。
He hedged his answer and wouldn't say it straight.
大雨で泥水が川を濁した。
Heavy rain muddied the river.
はっきり返事をせず言葉を濁すのは失礼だ。
It's rude to be vague and hedge instead of giving a clear answer.