caught

The verb 'catch' entered Middle English from Anglo-Norman and Old Northern French 'cachier', meaning "to chase, capture", which itself derived from Vulgar Latin captiāre, an alteration of Latin 'captāre', meaning "to try to seize, to catch at". This Latin verb is a frequentative of 'capere', meaning "to take, seize". The irregular past tense 'caught' developed in Middle English, influenced by the related Old English verb 'lǣccan' (to seize) and its past tense 'lǣhte'. The phonological evolution from the expected 'catched' to 'caught' represents a complex historical interaction between the imported French/Latin root and native Germanic sound patterns, resulting in a suppletive form that is now lexically fixed.

The word 'caught' is an irregular past tense and past participle form of the verb 'catch'. It is not productively formed from separable morphemes in modern English.