The most common and most likely answer to this crossword clue is the 7 letter word CREEPER
I've seen this crossword clue in The Daily Telegraph
C
R
E
E
P
E
R
More clues leading to the result CREEPER
- American native with a soft-soled shoe
- Climber and soldiers look cold on ascent
- Slowly, stealthily I move here, peer coyly over walls
- Engineers look closely around upturned trailer
- Toad climbing on plant
- Perhaps Virginia is a sycophant
- Ivy? Teacher’s pet, little hesitation!
- Estuary cut through low-lying plant
- During brief recreation, fellow turned to a soft-soled shoe
- Climber and sycophant will be seen by the Queen
Buddy explains!

The straight part
We know that "Ivy" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case ivy = creeper.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 CREEPER mean?
CREEPER noun- A person or a thing that crawls or creeps.
- (often in the plural) A one-piece garment for infants designed to facilitate access to the wearer's diaper.
- A device which allows a small child to safely roam around a room from a seated or standing position.
- A metal plate with spikes, designed to be worn with shoes to prevent slipping.
- A spur-like device strapped to the boot to facilitate climbing.
- (chiefly in the plural) A small low iron, or dog, between the andirons.
- An instrument with iron hooks or claws for dredging up items from a well or other water.
- Any device for causing material to move steadily from one part of a machine to another, such as an apron in a carding machine, or an inner spiral in a grain screen.
- Any plant (as ivy or periwinkle) that grows by creeping; especially a climbing plant of the genus Parthenocissus.
- A treecreeper.
- A small four-hooked grapnel used to recover objects dropped onto the sea bed.
- The lowest gear of a tractor or truck.
- A low-profile wheeled platform whereupon an auto mechanic may lie on their back and gain better access to the underbody of a vehicle.
- A person who creeps people out; a creepy person.
- A kind of shoe, usually with a suede upper and a thick crepe sole, associated with various 20th-century subcultures.
- A ball that travels low, near ground level.