1 C1 neutral
To grow or extend in an upward direction, used of plants, structures, or shadows.
"The young saplings lengthened up quickly in the first spring sunshine."
inseparable
lengthen up
C1 neutral separable transitive/intransitive
To grow or extend upward, or to make something taller or longer in the upward direction.
In plain English
To get taller or to make something longer by going upward.
What does "lengthen up" mean?
One main meaning — here's how to use it.
Literal vs figurative
Words literally mean
To extend in an upward direction.
Actually means
To get taller or to make something longer by going upward.
Usage tip
Less common than 'lengthen out'. Used to describe plants growing taller, shadows elongating upward, or garments being altered to be taller at the top. Rare in everyday speech.
Words that pair with "lengthen up"
Natural word combinations native speakers use most often.
plant stem shadow garment structure
How to conjugate "lengthen up"
The five tense forms you'll use most often.
Base
lengthen up
I/you/we/they
3rd person
lengthens up
he/she/it
Past simple
lengthened up
yesterday
Past participle
lengthened up
have + pp
-ing form
lengthening up
continuous
Hear "lengthen up" in the wild
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Other ways to say "lengthen up"
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