Where does the "t" in some words like "night" and "fight" come from?

Question

The question is on the words with a word-final "ght", such as in "fight" and "wight", which are quite mysterious, I hope to know the connections among these "ght" words.

The question comes from the fact that I just don't understand the "t" in the PGmc origin "nakht-", "fekhtanan" and "wekhtiz" stand for, because I can not find the descriptions about the function or meaning of the PGmc or PIE morpheme "t".

So the ultimate question is: What is the historical function about the "t" mentioned in the words(with these old language words) above?

night

O.E. niht (W.Saxon neaht, Anglian næht, neht) "night, darkness;" the vowel indicating that the modern word derives from oblique cases (gen. nihte, dat. niht), from P.Gmc. *nakht- (cf. O.S., O.H.G. naht, O.Fris., Du., nacht, Ger. Nacht, O.N. natt, Goth. nahts), from PIE *nekwt- "night" (cf. Gk. nuks "a night," L. nox, O.Ir. nochd, Skt. naktam "at night," Lith. naktis "night," O.C.S. nosti, Rus. noch', Welsh henoid "tonight"), according to Watkins, probably from a verbal root *neg- "to be dark, be night." For spelling with -gh- see fight.

fight

O.E. feohtan "to fight" (class III strong verb; past tense feaht, pp. fohten), from P.Gmc. *fekhtanan (cf. O.H.G. fehtan, Ger. fechten, M.Du., Du. vechten, O.Fris. fiuhta "to fight"), from PIE *pek- "to pluck out" (wool or hair), apparently with a notion of "pulling roughly" (cf. Gk. pekein "to comb, shear," pekos "fleece, wool;" Pers. pashm "wool, down," L. pectere "to comb," Skt. paksman- "eyebrows, hair").

Spelling substitution of -gh- for a "hard H" sound was a Middle English scribal habit, especially before -t-. In some late Old English examples, the middle consonant was represented by a yogh. To fight back "resist" is recorded from 1890.

wight

O.E. wiht "living being, creature," from P.Gmc. *wekhtiz (cf. O.S. wiht "thing, demon," Du. wicht "a little child," O.H.G. wiht "thing, creature, demon," Ger. Wicht "creature, infant," O.N. vettr "thing, creature," Swed. vätte "spirit of the earth, gnome," Goth. waihts "something").

The only apparent cognate outside Gmc. is O.C.S. vešti "a thing." Not related to the Isle of Wight, which is from L. Vectis (c.150), originally Celtic, possibly meaning "place of the division."

Answer 1

One thing to remember about English spelling is that for the most part it is "frozen", and reflects the Middle English pronunciation. Another thing to remember is that there has never been a standardized spelling for English, and individual judgment, errors, and a variety of dialects have played a large role in how words are spelled. So every question about English spelling has to be considered in light of these two major issues.

Night, fight, and wight are all pronounced with a final /-aɪt/ in Modern English. Their < -ght > spelling reflects the Middle English pronunciations, which had a final /-ixt/. (The digraph < gh > in MidEng represented the sounds /x/ or /ç/, which were also variously spelled < h >, < ch >, < ȝ >.)

The reason the three words are spelled similarly in Modern English is that they rhymed in Middle English. The reason they rhymed in Middle English despite differing etymologies is that they underwent regular predictable phonological mergers:

• In Proto-Germanic these words were:

  • nɑxt-s 'night n.' < PIE *nokʷts
  • wiht-iz 'creature, person, thing n.' < PIE *wekti-
  • fex-t ɑn 'to comb wool, to struggle v.' < PIE *pek-. The /t/ came from the personal suffix on the verb.

• In Old English the three rhymes were not yet homophones. The /a/ in the night etymon had raised to /i/ under palatal umlaut, causing it to rhyme with wight:

  • niht /niht/ [niçt] 'night'
  • wiht /wiht/ [wiçt] 'wight'
  • but feoht /feoht/ [feoxt] 'fight n.'

• By Middle English the rhymes were all homophonous in /-iːht/. This was due to the effects of raising on the sequence /eoh/ to /ih/ in a series of steps: /eoh/ -> /øːh/ -> /eːh/ -> /iːh/; thus:

  • niht -> night /niːht/
  • wiht -> wight /wiːht/
  • and feoht -> fight /fiːht/

• In the English Great Vowel Shift, Middle English /iː/ diphthongized to [ɪi], then became [əɪ], and finally Modern English [aɪ]. Non-initial /h/ was lost. This led to:

  • night /naɪt/
  • wight /waɪt/
  • fight /faɪt/

QED

Answer 2

That is just a /t/ sound, not a morpheme. This makes as much sense as asking where the /n/ in near and nickel come from.

The words night, fight, and others like right historically had a fricative before the /t/, and words like through and rough ended in that fricative (compare English through [θɹu:] with German durch [dʊɐ̯çç]).

In Middle English, the fricative likely varied regionally, and it inconsistently either deleted (through, plough, night, fight, wight, drought) or became [f] (rough, trough, enough) in Modern English.

Just because night and fight end in -ght it does not mean that sound was one morpheme. It just happens to be the consonant cluster they ended in.

Answer 3

At least, in night the "t" came from the original PIE word for night, noqu̯ts.