adverb
1Military
With less than the usual or required personnel, equipment, or resources.2Of a mixture, compound, or preparation: under the usual, appropriate, or expected potency or degree of concentration.
adjective
1Having less than the usual, appropriate, or expected potency or degree of concentration.
2Military
Having less than the usual or required personnel, equipment, or resources.
Origin
Mid 19th century; earliest use found in Lancaster Gazette. From under- + strength.
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