The most common and most likely answer to this crossword clue is the 9 letter word ESSENTIAL
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More clues leading to the result ESSENTIAL
- Basic lease isn't up for renewal
- Fundamental crack lets in sea
- European steals in, after forging key
- Eat in less irregularly — that's vital!
- . Circulating salient points in advance is crucial
- In distress it’s seen by almost everybody as absolutely necessary
- Vital European killers finally dispatched one gangster
- Sees new Latin translation as vitally important
- Vitally important German city starts to turn into a liability
- Head off in temper — it’s over a lost key
Buddy explains!

The straight part
We know that "Fundamental" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case fundamental = essential.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 ESSENTIAL mean?
ESSENTIAL noun- A necessary ingredient.
- A fundamental ingredient.
- Necessary.
- Very important; of high importance.
- Necessary for survival but not synthesized by the organism, thus needing to be ingested
- Being in the basic form; showing its essence.
- Really existing; existent.
- Such that each complementary region is irreducible, the boundary of each complementary region is incompressible by disks and monogons in the complementary region, and no leaf is a sphere or a torus bounding a solid torus in the manifold.
- Idiopathic.