ultralow
Barely above zero
Ultralow describes something extremely low, beyond what would ordinarily be called low: ultralow interest rates, ultralow emissions, ultralow temperatures.
The prefix ultra- intensifies low to suggest levels at or near the minimum of a scale.
Common in technical and scientific contexts where precise gradations matter.
Too small to consider
- traceMinute remnant or pursue
- infinitesimalQuantity approaching zero
- vanishingCeasing to be visible
- minusculeExtremely small in size
microscopic · threshold · residual · nominal · baseline · floor · limit · undetectable
Sound below 20 Hz
- subsonicBelow sound's speed
- hertzFrequency measurement unit
- vibrationRapid oscillating movement
- oscillationRepeated back-and-forth movement
wavelength · seismic · rumble · inaudible · resonance · bass · radio wave · electromagnetic
Theoretical minimum temperature
- cryogenicExtremely low temperature
- superconductivityLossless current flow phenomenon
- liquid nitrogenCryogenic form of air's main component
- liquid heliumSupercooled element in fluid state
cryostat · superfluidity · cryopreservation · vitrification · cryoprotectant · thermometry · cooling · refrigeration
Environment-harming agent
- carbonSixth element, atomic symbol C
- sulfurYellow combustible element
- particulateTiny suspended matter
- exhaustUse up entirely
tailpipe · clean energy · environmental · regulation · standard · hybrid · electric vehicle · green
negligible
Too small to consider
- traceMinute remnant or pursue
- infinitesimalQuantity approaching zero
- vanishingCeasing to be visible
minuscule · microscopic · threshold · residual · nominal · baseline · floor · limit · undetectable · marginal
infrasound
Sound below 20 Hz
oscillation · wavelength · seismic · rumble · inaudible · resonance · bass · radio wave · electromagnetic · communication
absolute zero
Theoretical minimum temperature
- cryogenicExtremely low temperature
- superconductivityLossless current flow phenomenon
- liquid nitrogenCryogenic form of air's main component
liquid helium · cryostat · superfluidity · cryopreservation · vitrification · cryoprotectant · thermometry · cooling · refrigeration · heat exchange
pollutant
Environment-harming agent
- carbonSixth element, atomic symbol C
- sulfurYellow combustible element
- particulateTiny suspended matter
exhaust · tailpipe · clean energy · environmental · regulation · standard · hybrid · electric vehicle · green · sustainable
- ultra-ultraviolet, ultrasound, ultramarine, ultrathin, ultrabright
ultralowultrahigh
Extremely elevated degree
sky-high · superhigh · astronomical · stratospheric · elevated