/θruː/
[preposition] Moving in one side and out the other side of something, or from the beginning to the end of something. It can also mean by means of, or because of, a particular thing or person.
'Through' once had a silent ghost — a 'gh' that used to be a real, scratchy sound at the back of the throat.
The word 'through' is one of the oldest words in the English language, stretching back to Old English in the form 'þurh', where the letter 'þ' (called a thorn) represented the 'th' sound. Its meaning was essentially the same as today — passing in one side and out the other, or from start to finish. The word belonged to the everyday core of the language, used by ordinary Anglo-Saxon speakers to describe movement, passage, and means. It was never borrowed from another language; it grew from the soil of the Germanic world.
Further back, Old English 'þurh' traces to Proto-Germanic '*þurhw', which also gave rise to Old High German 'durh', Old Saxon 'thurh', Old Frisian 'thruch', and Gothic 'þaírh'. All of these forms carry the same basic idea of passing across or penetrating a space. Moving even further back, linguists connect this Proto-Germanic root to the Proto-Indo-European root '*tr̥h₂-', which carried the sense of passing through or crossing over. This deep ancestral root is also related to Latin 'trans' (across), which passed through Old French as 'trans-' into English words like 'transport', 'translate', and 'transfer'. So 'through' and 'transport' are, in a sense, very distant cousins.
The spelling of 'through' has a remarkable and confusing history. In Middle English, the word appeared in dozens of different forms — 'thurgh', 'thrugh', 'thorow', 'thorugh', and many others. The written language was not yet standardised, and scribes spelled the word the way it sounded in their own regional dialect. The 'gh' combination in English once represented a real consonant sound — a guttural, rasping sound made at the back of the throat, similar to the 'ch' in the Scottish word 'loch' or the German 'Bach'. By the late medieval period, this sound had disappeared from most English dialects, leaving behind a silent 'gh' that still sits in the spelling like a fossil.
The modern spelling 'through' was largely fixed by early printers in the 15th and 16th centuries, who were trying to bring consistency to the written language. Unfortunately, consistency did not always match pronunciation, and 'through' became one of English's most notorious examples of a word that looks nothing like it sounds. The word rhymes with 'blew' and 'clue', despite ending in '-ough' — a combination that is also pronounced differently in 'though', 'thought', 'tough', 'cough', and 'bough'. Each of these words preserves a different historical pronunciation of that same silent cluster.
Over the centuries, 'through' has also developed into an adverb ('I read the whole book through'), an adjective in informal speech ('I'm through with that job'), and even a shortened spelling — 'thru' — which appeared in American English and is now widely used in casual writing and commercial signage. This informal variant is not laziness; it is actually a more logical spelling, stripping away centuries of silent letters to reveal the word's true sound. Whether written as 'through' or 'thru', the word remains one of the most used in the English language, quietly connecting beginnings to ends and one side to another, just as it has done for over a thousand years.