The practice of exploring drains, tunnels, or sewers(noun)
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Use "draining" in a sentence
"What is advanced as the main advantage of trench-ploughing in the first passage -- that it can be safely done without previous draining, is in the second wholly discarded by the advice, _never to trench-plough without previous draining_."
"With short-term draining operations and long-term water-management projects under way, "we have high confidence that this will not repeat," Deputy Prime Minister Kittiratt Na-Ranong said in an interview at the Asia-Pacific Economic Cooperation summit here."
"Signs of infection at the site (red, painful, warm to the touch and/or pus draining from the sting area, fever)."