The most common and most likely answer to this crossword clue is the 7 letter word SURNAME
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More clues leading to the result SURNAME
- Appellation of vase, outwardly identical
- Handle of identical large pot’s broken
- Farmer, say, succeeded spreading manure
- Family handle one leaving South American country
- Country ignores opening of Indiana Jones, perhaps
- Chap turns up with certain clothing — it’s passed down in the family
- Potential follower of 23 is certain to accommodate guy on the way up
- Inheritance from father certainly is holding chap up
- Something one gets from father certainly holding chap back
- Family label certain to get man drunk inside
Buddy explains!

The straight part
We know that "tag" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case tag = surname.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does SURNAME mean?
SURNAME noun- An additional name, particularly those derived from a birthplace, quality, or achievement; an epithet.
- An additional name given to a person, place, or thing; a byname or nickname.
- The name a person shares with other members of that person's family, distinguished from that person's given name or names; a family name.
- (Classical studies) The cognomen of Roman names.
- A clan.
- To give a surname to.
- To call by a surname.