title: Efficient way to drop a row from Dataframe A if an element equals an element in Dataframe B
body: <p>I have a column in Dataframe B that contains elements I wish to drop from Dataframe A, should A contain them. I wish to drop the entire row from A.</p>
  
  <p>I'm not new to programming but I am learning the extensive pandas library. From what I've seen, this can't be in any way efficient or proper. </p>
  
  <pre><code>for i in range(0,106):
      for j in range(0,171):
          if dfB.iloc[i,2] == dfA.iloc[j,0]:
              dfA.drop(j, inplace=True)
  </code></pre>