Definition of irregular verb in US English:

irregular verb

noun

Grammar
  • A verb that does not follow the normal pattern of inflection.

    ‘there are some differences in irregular verbs between British and American English’
    • ‘At a certain age children use the regular past tense for irregular verbs: "I digged a hole."’
    • ‘Many irregular verbs exhibit changes in the middle vowel for one or both of the last two principal parts (sing, sang, sung) and have an en inflection for the ed participle (speak, spoke, spoken).’
    • ‘Some irregular verbs also have regular forms: sew, sewed, sewn but also the regular sew, sewed, sewed.’
    • ‘A clue comes from the fact that irregular verbs are often the most frequently occurring verbs.’
    • ‘Unlike regular verbs, irregular verbs (about 150 in all) do not have past forms which can be predicted:’
    • ‘When she comes to me with questions about genitives and datives and irregular verbs, I feel useful again, the custodian of an ancient wisdom handed down from generation to generation.’
    • ‘Learning the many different conjugations of Spanish irregular verbs is possibly the most difficult part of learning Spanish for most students.’
    • ‘There is a comprehensive but compact explanation of grammar, including tables and irregular verbs.’
    • ‘Another wonderful aspect of Arabic is that it doesn't have irregular verbs, unlike, for example, French.’
    • ‘In some ways, English is highly unsuited to its role; it has 200 irregular verbs, where Swahili, for example, has none.’