on the half hour

on the half hour — idiom

1. happening at 30 minutes past every hour — for example, a bus that departs at 10:

1.idiomB1
Definition

happening at 30 minutes past every hour — for example, a bus that departs at 10:30, then 11:30, then 12:30, repeating this pattern through the day.

Example

Buses to the city centre leave on the half hour all morning.

scheduling pattern: [transport] + leave + on the half hour

The old clock in the square chimes on the half hour without fail.

Common collocations
  • leave on the half hour
  • depart on the half hour
  • run on the half hour
  • chime on the half hour
Synonyms
Antonyms
  • on the hour

    at the top of each hour (12:00, 1:00, etc.), not at the half-past point

Grammar Patterns

[transport/service] + leave/run/depart/arrive + on the half hour

Usage Note

Used with scheduling verbs such as leave, depart, arrive, start, run, and be broadcast. The phrase describes a pattern that repeats at every half-past mark, not a single one-off time.

Common Mistakes

The train leaves at half past.
The train leaves on the half hour.
'at half past' needs a specific hour (at half past ten); 'on the half hour' means at every half-past mark without naming the hour.
Buses depart on half hour.
Buses depart on the half hour.
the fixed phrase always includes 'the' before 'half hour'.

2. taking place exactly thirty minutes after the start of a sports match — for exam

2.idiomC1
Definition

taking place exactly thirty minutes after the start of a sports match — for example, a goal scored at the 30-minute mark of a football game or a substitution made at that point.

Example

Amara curled a free kick past the keeper on the half hour to level the score at one apiece.

sports: score + on the half hour

Dimitri was substituted on the half hour after a heavy tackle left him limping badly.

sports: passive, be substituted + on the half hour

Common collocations
  • score on the half hour
  • concede on the half hour
  • be substituted on the half hour
Synonyms

Grammar Patterns

[player/team] + score/concede + on the half hour

Usage Note

Restricted to sports commentary, especially football and rugby. Refers specifically to the 30-minute point measured from kick-off or the start of play, not from a restart or the beginning of the half.

Common Mistakes

The team scored on the half hour of the second half.
The team scored on the half hour.
'on the half hour' is measured from the start of the match; for a goal 30 minutes into the second half, say 'at the 75th minute' or similar.

Synonym discussion

Sense: idiom/1

'On the half hour' means at the 30-minute mark of every hour as a repeating pattern (buses, chimes, news bulletins). 'On the hour' is its counterpart for the top of each hour — a clock striking at 12:00, 1:00, and so on. 'At half past' is different because it requires naming a specific hour (at half past three) and refers to a single time, not a schedule that repeats. Compare: 'The bus leaves on the half hour' (every 30-minute mark through the day) versus 'The bus leaves at half past ten' (one specific departure). In everyday speech, 'on the half hour' is most natural for describing recurring transport or broadcast schedules.

on the hourat half past

Etymology

English

Formed by combining 'half hour' (the midpoint of an hour) with the scheduling pattern 'on the hour.' The phrase emerged in the context of public transport timetables and radio broadcasting schedules during the 19th and early 20th centuries, when regular clock-face departures became standard. The sports sense developed later as a specialised extension in British football and rugby commentary.