Home / Words / build upNo. 0047

build up

/ˌbɪld ˈʌp//ˌbɪld ˈʌp/·phrasal verb
to increase, develop, or strengthen something gradually over time
Fig. 1 — A line of fresh mortar is buttered along the top, and a brick is pressed into it and tapped down level with the handle — then another beside it, then another, until the row runs the whole width.
01Definition

To build up is to increase or strengthen something step by step until it amounts to something solid — reserves, muscle, momentum, a reputation, or the tension before a release. It is the hands-on, everyday twin of accumulate: where things accumulate almost on their own, you build up by adding deliberately, one layer onto the last. The phrasal verb leans toward development and strength, and it cuts both ways — you can build up savings and stamina, or let pressure build up until something finally gives.

02In use
  • iAthletes build up their stamina over months of steady training, not in one brutal session.
  • iiSilt builds up behind the dam until engineers deplete the reservoir to flush it out.
  • iiiA small shop can build up a loyal following, as long as its quality does not diminish.
03Collocations
  • build up reserves
  • build up strength
  • build up momentum
  • build up tension
  • build up a reputation

Family buildup (noun) · built-up (adjective)

04Relations

=accumulate, develop, strengthen, expand, amass

≠deplete, diminish, erode

05Compared
PairThe difference
build up vs accumulatethe formal verb for an amount creeping up → accumulate; the plain phrasal for developing something → build up.
build up vs amassa big quantity gathered on purpose → amass; steadily developing or strengthening → build up (amass wealth, build up muscle).
build up vs collectdevelop or strengthen the whole → build up; choose and keep its parts → collect (build up a collection by collecting items).
build up vs depletea store raised and strengthened → build up; drawn down to nothing → deplete.
build up vs dispersesomething gathers and grows → build up; a mass breaks apart and spreads → disperse.

Also compared with dissipate, garner, gather, pile up

06TOEFL & IELTS

An everyday phrasal verb that earns its place in TOEFL/IELTS speaking and writing: 'reserves build up', 'pressure builds up', 'build up the argument gradually'. The noun is written as one word — 'a buildup of traffic' — while the verb is two. It is less formal than accumulate but more vivid than 'increase', and it collocates widely: strength, momentum, tension, resistance, a following. Watch the charged sense — tension or pressure building up often signals a turning point in a reading passage.

07Asked
Is it 'buildup', 'build-up' or 'build up'?
The verb is always two words: 'pressure will build up'. The noun closes the gap — American style prefers one word ('a buildup of traffic'), British style keeps the hyphen ('a build-up of traffic'). The test is grammatical: if you can put 'a' or 'the' in front of it, close it up or hyphenate; if it has a subject doing it, keep it open.
Is 'build up' a separable phrasal verb?
Yes — 'build up your strength' and 'build your strength up' are both correct, and a pronoun object must go in the middle: 'build it up', never 'build up it'. That mobility is the everyday proof you are holding a phrasal verb, not the noun: nouns don't let you park a pronoun inside them.
What does 'build up to' mean?
To move gradually toward a peak or a moment: a film builds up to its reveal, a training plan builds up to race distance, and someone nervous 'builds up to' a difficult conversation. The to marks a destination — the buildup is the slope, and whatever follows to is the summit it was climbing toward.
What does 'the build-up' mean before an event?
The charged stretch of accumulation just before something happens — 'the build-up to the final' is sports media's fixture, and pressure, tension and traffic all get build-ups of their own. The scene above shows the mechanics at wall scale: row after staggered row, nothing poured at once, until the top stands at the line.
What is the difference between build up and accumulate?
The short tell: building up is done with your sleeves rolled — deliberate, layer on layer — while accumulation can simply happen while nobody watches. That contrast and this phrasal verb's eight other pairings, from amass to deplete, each have a side-by-side page in the 'Compared' list above.