The most common and most likely answer to this crossword clue is the 7 letter word ISOTOPE
I've seen this crossword clue in The Guardian
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More clues leading to the result ISOTOPE
- Element the same, only different one old poet’s misrepresented
- I really put the sauce away in elementary form
- Something at the atomic level breathes oxygen over shark
- Priest interrupts awfully otiose element of one mass
- Elemental form is uppermost in poet’s heart.
- Type of atom: is oxygen best to get energy?
- One’s nothing to drink that might be radioactive
- Imogen’s confession of alcoholism, in one of several forms
- Then beat bad grade after one term in chemistry
- International Standard raised European drug as tracer?
Buddy explains!

The straight part
We know that "term in chemistry" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case term in chemistry = isotope.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 ISOTOPE mean?
ISOTOPE noun- Any of two or more forms of an element where the atoms have the same number of protons, but a different number of neutrons within their nuclei. As a consequence, atoms of isotopes will have the same atomic number but a different mass number.
- To define or demonstrate an isotopy of (one map with another).