ENGLISH
REFERENCE

insufficient

adj.
US //ˌɪnsəˈfɪʃənt// UK //ɪnsəfˈɪʃənt// in·suf·fi·cient
  1. 1 not enough quantity (adj.)
    B2 Upper Intermediate

    not having enough of something that is needed.

    lacking in the required amount or quantity to satisfy a particular purpose.

    Example

    The hikers had to turn back because they had insufficient water for the long trip.

    Example

    The project was delayed indefinitely due to insufficient funding from the primary investors during the first quarter.

    Usage

    Commonly followed by the preposition 'for' or an infinitive 'to' phrase.

    Pitfall
    The 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'.

  2. 2 not good enough (adj.)
    C1 Advanced Formal Academic

    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.

    Example

    The police released the suspect because there was insufficient evidence to charge him.

    Example

    The candidate's previous experience was deemed insufficient for the demands of a senior executive role in such a competitive market.

    Teacher's tip

    This sense is very common in legal, academic, and professional reports where 'not enough' might sound too casual.

Origin

From Middle French insufficient, from Latin insufficiens. See also in- + sufficient.

Word family

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