go

The English verb 'go' is among the most frequently used words in the language and one of the most etymologically remarkable.‍​‍​‍​‍​‌​‍​‌​‌​‌​‍​‌​‌​‌​‌​‌​‍​‍​‌​‍​‌​‌​‍​‍​‍​‌​‌​‍​‍​‍​‌​‍​‌ It descends from Old English 'gān,' from Proto-Germanic *gāną, which traces to the Proto-Indo-European root *ǵʰeh₁- meaning 'to leave' or 'to go away.' The verb has been in continuous use for well over a thousand years, but its history is far from simple.

The most striking feature of 'go' is its suppletion — the phenomenon whereby a verb's paradigm is assembled from pieces of originally unrelated words. In Modern English, the present tense 'go' and the past tense 'went' have no etymological connection. 'Went' comes from Old English 'wendan' (to turn, to wend one's way), the past tense of which was 'wende.' Over the course of the Middle English period, 'went' gradually replaced the original past tense of 'go,' which was 'eode' (sometimes 'yede' in Middle English). By the fifteenth century, 'eode/yede' had vanished from standard English, and 'went' had been fully absorbed into the paradigm of 'go.'

This kind of radical suppletion — where the past tense comes from a completely different verb — is rare across the world's languages. The closest parallel in English is 'be/was/were,' where 'be' derives from PIE *bʰuH-, 'was' from *h₂wes- (to dwell), and 'are' from *h₁es- (to be). But suppletion in a motion verb like 'go' is typologically unusual. The displacement happened because 'wendan' was semantically close to 'gān' (both could mean 'to go' in certain contexts), and the phonological distinctiveness of 'went' made it a more robust past-tense marker than the increasingly archaic-sounding 'eode.'

The PIE root *ǵʰeh₁- is not richly attested outside Germanic. Within the Germanic family, cognates include German 'gehen,' Dutch 'gaan,' Swedish and Danish 'gå,' Norwegian 'gå,' and the extinct Gothic form that appears to underlie the verb, though Gothic used a different primary verb for motion. Outside Germanic, possible cognates are debated, but Greek 'kikhánō' (to reach, to arrive at) has been proposed as a distant relation, as has the Greek form 'khōstai.'

The word 'ago' is itself a fossil of the verb 'go.' It comes from Middle English 'ago,' the past participle of 'agon' (to go away, to pass), from Old English 'āgān' — literally 'gone by.' When English speakers say 'three years ago,' they are literally saying 'three years gone by,' with 'ago' serving as an adverbialized past participle.

Phonologically, the development from Old English 'gān' (pronounced roughly /ɡɑːn/) to Modern English 'go' (/ɡoʊ/) reflects the Great Vowel Shift and the loss of the final nasal in the infinitive form. Middle English 'gon' or 'goon' shows the intermediate stage, with the long 'o' vowel that later diphthongized to the modern /oʊ/.

The semantic range of 'go' in Modern English is extraordinarily wide. Beyond simple motion, it covers functioning ('the car won't go'), becoming ('go mad,' 'go bad'), suitability ('anything goes'), attempts ('have a go'), and dozens of phrasal verb combinations ('go off,' 'go on,' 'go over,' 'go through'). This polysemy makes 'go' one of the most versatile words in the language — the Oxford English Dictionary devotes one of its longest entries to the verb, with over 400 distinct senses and sub-senses.

Historically, 'go' has always been one of the core verbs of English. It appears in the earliest Old English texts, including the Anglo-Saxon Chronicle and the poetry of the Exeter Book. Its stubborn irregularity — resisting the regularizing pressures that have smoothed most English verbs into a -ed past tense — is a sign of its sheer frequency of use. The most common words in any language are the last to be regularized, because speakers know their irregular forms too well to accept substitutes.