Opposite of "punctual"

[Tom]

Hi

I would like to know the opposite of the word punctual. Please see below:

1- Although his brother is regular and punctual, he is very irregular and unpunctual.

How does it sound to you?

Tom

[Tamara]

[DOlier]

There is no opposite word.
It depends on the context: one might say "not punctual"
"not very punctual" or "often late".

[Yankee]

Hi Tom

The usual opposite for punctual would be late.

I feel a little uncomfortable with "regular and punctual", so that makes saying the opposite even more difficult.

Exactly what tendency (of his personality/character) did you want to call "regular"?

Here is a suggestion:
Although his brother is very dependable and always punctual, he is quite undependable and frequently late.

Note to Tamara:
The standard word would be imprecise.

Amy

[Tamara]

[DOlier]

But …'non-standard' unprecise is also in use… in fact...
Take a look, for example, at the heading: http://www.webrankinfo.com/english/seo-news/topic-301.htm

Hi Tamara,
I think Yankee is correct. The term "unprecise" is not good English. However wrote the example you refer to is mistaken.

Art

[Tamara]

Hi dOlier,

Thank you very much for your thought.
_________________
It’s impossible to learn swimming without entering the water…

[Conchita]