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swear

v. · n.
US //ˈswɛɹ// UK //swˈeə// swear
Irregular verb past swore past participle sworn
  1. 1 to promise solemnly (v.)
    B1 Intermediate

    to make a serious or legal promise that something is true or that you will do something.

    to make a solemn or formal declaration, often invoking a deity or legal authority, to attest to the truth of a statement.

    Example

    I swear that I am telling the truth about what happened last night.

    Example

    The witness was required to swear an oath on the Bible before providing her testimony to the court.

    Usage

    often followed by a 'that' clause or an infinitive.
  2. 2 to use bad language (v.)
    B2 Upper Intermediate Informal

    to use rude, offensive, or angry words.

    to use profane, obscene, or offensive language, often as an expression of anger or frustration.

    Example

    He started to swear loudly when he dropped the heavy box on his foot.

    Example

    The coach was warned by the referee after he continued to swear at the players from the sidelines.

    Usage

    intransitive or followed by 'at' when directed at a person.
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  1. 3 to rely on something (v.)
    C1 Advanced Informal

    to believe strongly that something is effective or useful.

    to express great confidence in the effectiveness or value of a particular thing.

    Example

    My grandmother swears by honey and lemon whenever she has a sore throat.

    Example

    Many professional athletes swear by this specific recovery routine, claiming it significantly reduces the risk of muscle strain.

    Usage

    usually used in the phrasal form 'swear by'.
  2. 4 a rude word (n.)
    B2 Upper Intermediate British English Informal

    a rude or offensive word.

    an instance of profane or obscene language; a swear word.

    Example

    The young boy got in trouble for using a swear in front of his teacher.

    Example

    The script was edited for television to remove every swear and replace them with milder alternatives.

    Teacher's tip

    In American English, 'curse word' or 'profanity' is more common than using 'swear' as a noun.
Etymology 1

From Middle English sweren, swerien, from Old English swerian (“to swear, take an oath of office”), from Proto-West Germanic swarjan, from Proto-Germanic swarjaną (“to speak, swear”), from Proto-Indo-European *swer- (“to swear”). Cognate with West Frisian swarre (“to swear”), Saterland Frisian swera (“to swear”), Dutch zweren (“to swear, vow”), Low German swören (“to swear”), sweren, German schwören (“to swear”), Danish sværge, Swedish svära (“to swear”), Icelandic sverja (“to swear”), Russian свара (svara, “quarrel”). Also cognate to Albanian var (“to hang, consider, to depend from”) through Proto-Indo-European. The original sense in all Germanic languages is “to take an oath”. The sense “to use bad language” developed in Middle English and is based on the Christian prohibition against swearing in general (cf. Matthew 5:33-37) and invoking God’s name in particular (i.e. frequent swearing was considered similar to the use of obscene words).

Etymology 2

From the above verb, or from Middle English sware, from Old English swaru, from Proto-Germanic *swarō.

Etymology 3

From Middle English swere, swer, swar, from Old English swǣr, swār (“heavy, heavy as a burden, of great weight, oppressive, grievous, painful, unpleasant, sad, feeling or expressing grief, grave, slow, dull, sluggish, slothful, indolent, inactive from weakness, enfeebled, weak”), from Proto-West Germanic swār, from Proto-Germanic swēraz (“heavy”), from Proto-Indo-European *swer- (“heavy”). Cognate with West Frisian swier (“heavy”), Dutch zwaar (“heavy, hard, difficult”), German schwer (“heavy, hard, difficult”), Danish svær (“heavy, hard, severe”), Swedish svår (“heavy, hard, severe”), Latin sērius (“earnest, grave, solemn, serious”) and Albanian varrë (“wound, plague”).

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