Underpressure

Part of speech: adjective, adverb

Definitions

1. Feeling strain from urgent demands or threats ; having gas or fluid held at a pressure lower than the surrounding atmosphere
2. Experiencing heavy stress or obligation ; kept at a pressure beneath normal atmospheric levels, as in a vacuum or suction system
3. Being subjected to strain or intense demands ; operating at a reduced pressure that falls below the ambient air pressure

Etymology: "Underpressure" is a plain formation: the prefix "under-" attached to "pressure," with the sense "under strain" or "under heavy pressure." The prefix comes from Old English "under," which goes back to a Proto-Germanic root meaning "beneath" or "among," and it has been productive in English for over a thousand years, forming words such as "undergo" and "undertake." "Pressure" has a longer lineage. It descends from Latin "pressura," a noun built on "pressus," the past participle of "premere," meaning "to press." The Latin word passed into English through Old French, where the same sense of physical squeezing was already established, so the modern word carries both the literal idea of force applied to a surface and the figurative idea of stress or demand. Joining the two parts gives a compound that expresses a state of being squeezed from below or beneath a load. The word is a straightforward English compound, and its meaning follows directly from the parts.