I thought "a bit of" is generally used to show small amount of something, but does the phrase mean "a large amount of " occasionally?
If somebody says;
"That's a bit of an adjustment."
What does "a bid of" mean in the sentence?
Does it mean "a small amount of" adjustment, or "a large amount of" adjustment?
-------------------------------
My Oxford dictonary says;
[C] bit of sth
- a small amount or piece of sth
[sing.] a bit (of sth)
- a large amount
-------------------------------
Online Cambridge Dictionary says;
a bit of sth
- a slight but not serious amount or type of something:
e.g.
Maria's put on a bit of weight, hasn't she?
It's a bit of a nuisance.
He's a bit of a prat.
-------------------------------
I am becoming more and more confused.... ....by reading these dictionaries..........

Could you please explain the phrase for me?
Many thanks for your help in advance.