What's the pronunciation of 1点差?


Intuitively, I would guess it's 「いってんさ」, but I could image 「いちてんさ」just as
well.

For bonus points: is there any reference or dictionary that explains the
pronunciation of numbers with counters (beyond the obvious ones taught in
beginner's courses)?




I also believe it is いってんさ。

It means a one point difference (or gap)

一点、二点 etc ＝one point, two point etc

差＝difference, eg 差がある＝there is a difference or gap.

Possibly

> てんさ／点差 | the difference in points

is more common than 一点差 （？）eg:

> 2点の点差で負けた｜We lost the game by two points.
>
> ライオンズは点差を広げた｜The Lions widened their lead.

