Sometimes, at the left side of a Bible reference ('citation') that is given for an example-word at the left end of the table this notation cf appears.
This means that the Bible reference is not an exact one, the matching is not complete, but this bible reference is able to help the reader to get a good or a better understanding of what he is reading.
Let us look at N-t068
As a Bible citation of the first sample word we see [cf Dan 3:24]. Why this "cf"?
Because the noun supplied firstly as for a sample of the pattern does not appear as such in the Bible. But it deepens its roots into the Bible, in Dan 3:24. In this verse, however, we find this word spelled slightly differently: תְּוַהּ, third person singular masculine of the Past Peal, he was startled.
From this Aramaic verb form our Hebrew noun ptr N-t068 was formed or derived.