insufficient
- 01 B2 Upper Intermediate
not having enough of something that is needed.
lacking in the required amount or quantity to satisfy a particular purpose.
Simple“The hikers had to turn back because they had insufficient water for the long trip.”
In context“The project was delayed indefinitely due to insufficient funding from the primary investors during the first quarter.”
UsageCommonly followed by the preposition 'for' or an infinitive 'to' phrase.
PitfallThe food was insufficient for we all. The food was insufficient for all of us.Insufficient is an adjective; it describes the noun (food) and usually takes a prepositional phrase starting with 'for'.
SynonymsAntonyms - 02 C1 Advanced
not of a high enough quality or strength to do a job.
failing to meet a qualitative standard or lacking the necessary power or evidence to be effective.
Simple“The police released the suspect because there was insufficient evidence to charge him.”
In context“The candidate's previous experience was deemed insufficient for the demands of a senior executive role in such a competitive market.”
Teacher's tipThis sense is very common in legal, academic, and professional reports where 'not enough' might sound too casual.
SynonymsAntonyms
Usage insufficient evidence
“But in its May 2026 position statement , IAPMD noted that “there is insufficient evidence to conclude that histamine tolerance, mast cell activation, or related immune mechanisms are a primary cause of [pre-menstrual disorders]”.”
“Workers at Groundforce, who number 1,179 at Spain's second busiest airport, cite poor working conditions, physical fatigue, stress, unpaid overtime and insufficient rest periods as the reasons for holding the strike.”
From Middle French insufficient, from Latin insufficiens. See also in- + sufficient.
Etymology adapted from Wiktionary, available under CC BY-SA 4.0.