OpenEtymology

underweight

UKˌʌndəˈweɪtUSˌʌndərˈweɪt

Meaning

1adj

weighing less than is normal, healthy, or required

2v

to assign too low a weight or importance to; to underestimate

Structure

word structure
1
under
below
+
2
weight
heaviness

Usage

The doctor said the child was slightly underweight for his age.

Many investors underweight government bonds in their portfolios during periods of high inflation.

The airline's baggage policy charges a fee for overweight luggage but not for underweight bags.

Etymology

The word 'underweight' is a transparent compound formed within English from its native Germanic elements. The prefix 'under,' tracing back to Proto-Germanic under and ultimately Proto-Indo-European ndher- meaning "under," combines with 'weight,' from Old English wiht (thing, creature) and gewiht (weight), itself from the Proto-Germanic root wihtiz related to movement and lifting. The literal, physical sense of "below the standard weight" emerged logically from this combination. Over time, the term also developed a figurative, financial usage as a verb, meaning to assign insufficient importance or capital to an asset, extending the core idea of "deficiency in measure" from the physical to the abstract.

Analysis

Structure
under (below) + weight (heaviness)=underbelow+weightheaviness

- under: Old English; a preposition/adverb prefix meaning "beneath, below, or less than." - weight: Old English; a noun root derived from the concept of "heaviness" or "the measure of how heavy something is."

Underweight Meaning & Word Parts (under + weight) | OpenEtymology