eighth

IPA/eɪtθ/
KK[ˈetθ]IPA/eɪtθ/

eighth — ordinal number

1. used for referring to the number 8 in a sequence that puts things in order — for

1.ordinal numberA1
Definition

used for referring to the number 8 in a sequence that puts things in order — for example, the eighth person standing in a line, the eighth day of the month, or the eighth item on a list.

Example

Aarav celebrated his eighth birthday with a big party at the park near his house.

eighth + noun (birthday; ordinal position)

Quan lives on the eighth floor of the apartment building next to the river.

Common collocations
  • eighth birthday
  • eighth floor
  • eighth grade
  • eighth place
  • eighth time
  • eighth street
  • eighth day
  • eighth attempt

Grammar Patterns

the + eighth + noun

possessive + eighth + noun

Usage Note

Unlike cardinal numbers (eight, ten), ordinal numbers like eighth are almost always used with 'the' (the eighth day) or a possessive (his eighth birthday). One exception is in street names: Eighth Avenue.

Common Mistakes

She came in eight place in the race.
She came in eighth place in the race.
'Eight' is a cardinal number for counting; 'eighth' is an ordinal number for showing position.
This is my eightth birthday.
This is my eighth birthday.
When adding the ordinal suffix '-th' to 'eight', only one 't' is kept: eight + th = eighth.

eighth — noun

Word family

Synonym discussion

Sense: ordinal number/1

Eight is a cardinal number used for counting quantity: 'There are eight apples.' Eighth is the ordinal form, used to show position in a sequence: 'the eighth apple in the row.' The main error learners make is using 'eight' when they need 'eighth' (❌ 'eight floor' ✅ 'eighth floor'). A less common variant is 'eighthly', an adverb used mainly in formal or numbered lists ('Eighthly, we need to review the budget') — but in everyday English, 'eighth' as an ordinal is far more natural. For making lists, 'eighth' without '-ly' is preferred: 'Eighth, close the windows before you leave.'

eight ↗eighth ↗eighthly

Common collocations

Nouns

Phrases

  • the eighth to
  • an eighth of

Prepositions

  • eighth of
  • eighth in
  • eighth out of

Etymology

Proto-Indo-EuropeanProto-GermanicOld EnglishMiddle EnglishEnglish

Eighth comes from Old English 'eahtoþa', which was built from 'eahta' (eight) plus the ordinal suffix '-þa' (later '-th'). This pattern is shared with other Germanic languages: Old High German 'ahtodo', Gothic 'ahtuda'. The Proto-Indo-European root is '*oḱtṓwos' from '*oḱtṓ' (eight), related to Latin 'octavus'. The spelling with 'gh' (instead of 'h') appeared in Middle English under French influence.