underweight

under- +‎ weight.

underweight (comparative more underweight, superlative most underweight)

1. Of an inappropriately or unusually low weight.

   He's so underweight he's had to buy smaller clothes.

   He's thirty pounds underweight.

   The market trader was fined for selling underweight bags of fruit.

2. Not too heavy for an intended purpose.

   The suitcase is just slightly underweight; I'll let it on the plane.

3. (finance) Being less invested in a particular area than market wisdom suggests.

   The fund is underweight in mining.

   • 2011, Murdoch, S. Foreigners back for Aussie stocks, The Australian

     "It's a long-run trend of foreign investors -- typically being underweight the banking sector in Australia," Mr Baker said.

• (antonym(s) of “of low weight”): overweight
• (antonym(s) of “not too heavy”): overweight

underweight (countable and uncountable, plural underweights)

1. (uncountable) The state or quality of being underweight.
   • 1996, United States Institute of Medicine Committee on Scientific Evaluation of WIC Nutrition Risk Criteria, WIC Nutrition Risk Criteria: A Scientific Assessment, National Academies Press, →ISBN, page 110,

     Underweight reflects the body’s thinness, but the term does not necessarily imply the nature and causes of underweight.

2. (countable) An underweight person.
3. (countable, finance) An underweight investment.
   • 2004, Bob Litterman, Modern Investment Management: An Equilibrium Approach, page 198:

     Further, structured managers usually attempt to hit their lower targets by relying on a relatively large number of small active deviations (i.e., overweights and underweights).

   • 2011, Peter L. Bernstein, Capital Ideas Evolving, page 230:

     Consider a conventional long-only portfolio with underweights on holdings the investment manager does not like and overweights on holdings the manager does like.

• (antonym(s) of “state or quality”): overweight
• (antonym(s) of “underweight person”): overweight

underweight (third-person singular simple present underweights, present participle underweighting, simple past and past participle underweighted)

1. (transitive) To underestimate the weight of.
2. (transitive) To give insufficient weight to (a consideration); to underestimate the importance of.
3. (transitive, finance) To invest in less than conventional wisdom would dictate.
   • 2009, Philip Lawton, Todd Jankowski, Investment Performance Measurement, page 419:

     Although the portfolio overweights the German market, it underweights German marks.