The most common and most likely answer to this crossword clue is the 8 letter word GRADIENT
I've seen this crossword clue in The Guardian
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More clues leading to the result GRADIENT
- Reading about peak in Tanzania, might that be steep?
- It’s inclined to go west, protected by allowance
- Rise in endowment interrupted by decease
- Incline to admit having to go inside
- An inclination to wither away in allotment
- Garden — it is made awkward by this slope
- Inclination of duke that is seen in funds for student
- Drop off in allowance for slope
- Hills have this danger? It requires disentangling
- Slope in garden altered to accommodate one plant finally
Buddy explains!

The straight part
We know that "slope" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case slope = gradient.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 GRADIENT mean?
GRADIENT noun- A slope or incline.
- A rate of inclination or declination of a slope.
- Of a function y = f(x) or the graph of such a function, the rate of change of y with respect to x that is, the amount by which y changes for a certain (often unit) change in x equivalently, the inclination to the X axis of the tangent to the curve of the graph.
- The rate at which a physical quantity increases or decreases relative to change in a given variable, especially distance.
- A differential operator that maps each point of a scalar field to a vector pointed in the direction of the greatest rate of change of the scalar. Notation for a scalar field φ: ∇φ
- A gradual change in color. A color gradient; gradation.
- Moving by steps; walking.
- Rising or descending by regular degrees of inclination.
- Adapted for walking, as the feet of certain birds.