pünktlich
punctual / on time
Arriving, beginning, or taking place exactly at the agreed or scheduled time; neither too early nor too late.
Der Zug nach Hamburg fuhr pünktlich um 10:05 Uhr ab.
The train to Hamburg departed on time at 10:05.

punctual / on time
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punctual / on time
Arriving, beginning, or taking place exactly at the agreed or scheduled time; neither too early nor too late.
Der Zug nach Hamburg fuhr pünktlich um 10:05 Uhr ab.
The train to Hamburg departed on time at 10:05.

The word is derived from 'der Punkt' (the point). To be 'pünktlich' (punctual/on time) therefore means to arrive exactly at the 'point' in time, that is, exactly at the agreed time.
Wir müssen auf den Punkt genau um 15:00 Uhr starten.
We have to start exactly on the dot at 3:00 p.m.
'Pünktlich' (punctual/on time) is very often used as an adverb to describe a verb. It answers the question 'When?'. In this function, it remains unchanged and is not declined.
Bitte kommt morgen alle pünktlich zum Treffen.
Please all come to the meeting on time tomorrow.
Punctuality is an important value in German professional and everyday life. Being late is often seen as rude or unreliable.
Für das Vorstellungsgespräch ist es besonders wichtig, pünktlich zu sein.
For the job interview, it is especially important to be punctual.
late
'spät' and 'pünktlich' both often refer to fixed appointments or agreed times. 'spät' means that someone or something arrives or begins after that time. 'pünktlich' means that someone or something arrives or begins exactly at the agreed time, so not too late and not too early. Learners may confuse the words because both can appear in sentences like 'zum Termin kommen' (to come to an appointment). A practical rule is: someone who is 'pünktlich' keeps to the time; someone who is 'spät' has gone past the time.

Sie ist pünktlich, weil sie jeden Morgen einen Zug früher nimmt.
She is on time because she takes an earlier train every morning.
Heute wird Lukas spät zum Kurs kommen, weil der Bus nicht fährt.
Today Lukas will come late to the course because the bus isn't running.