1 B2 neutral
(Of an animal, especially a horse) To rise up onto its hind legs.
"The stallion reared up dramatically when the starting gun fired."
inseparable
rear up
B2 neutral inseparable intransitive
To rise up on hind legs (of animals), or to appear suddenly and imposingly; also used of problems that arise unexpectedly.
In plain English
To stand up tall suddenly (like a horse standing on its back legs), or for a problem to suddenly appear.
What does "rear up" mean?
3 meanings, ordered from most common to least. Color-coded by CEFR level.
2 B2 idiomatic neutral
To appear suddenly in a dramatic, threatening, or imposing way (of a problem, obstacle, or structure).
"Just when everything seemed to be going well, a new complication reared up to delay the project."
inseparable
3 B2 neutral
To rise up steeply or to tower upward (of a building, cliff, or landscape).
"The castle walls reared up above the village, casting long shadows across the rooftops."
inseparable
Literal vs figurative
Words literally mean
To raise the rear (back) end upward, as a horse rises on its hind legs.
Actually means
To stand up tall suddenly (like a horse standing on its back legs), or for a problem to suddenly appear.
Usage tip
The animal sense (horse rearing up) is the most physical and literal. The figurative sense is common in journalism and discussion of problems: 'a crisis reared up'. The phrase 'rear its ugly head' is a fixed idiom related to this meaning.
Words that pair with "rear up"
Natural word combinations native speakers use most often.
horse snake problem issue obstacle crisis head
How to conjugate "rear up"
The five tense forms you'll use most often.
Base
rear up
I/you/we/they
3rd person
rears up
he/she/it
Past simple
reared up
yesterday
Past participle
reared up
have + pp
-ing form
rearing up
continuous
Hear "rear up" in the wild
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Other ways to say "rear up"
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Keep exploring
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