The best way to do this:

Open a Coinbase wallet https://www.coinbase.com
Link Coinbase to your bank account
Withdraw your USD or even Bitcoin / Ethereum / Litecoin from Poloniex and send it to your Coinbase wallet
From your #Coinbase wallet, you can transfer your USD directly to your bank account

I know it should be made easier, but this is the easiest method at the moment!

Any questions? Please follow me, you can talk to me on Steem.Chat or mention me in a comment on this post.

RE: How to withdraw USD from poloniex