Those who insist that “scan” can never be a synonym of “skim” have lost the battle. It is true that the word originally meant “to scrutinize,” but it has now evolved into one of those unfortunate words with two opposite meanings: to examine closely (now rare) and to glance at quickly (much more common). It would be difficult to say which of these two meanings is more prominent in the computer-related usage, to “scan a document.”
That said, it’s more appropriate to use “scan” to label a search for specific information in a text, and “skim” to label a hasty reading aimed at getting the general gist of a text.
On the podcast this week we conclude our conversation about contranyms, words that mean two very different things at once.