Does this sentence have any special meaning in Norwegian other than the literal one?
It has no special meaning.
"Ban.." rooted words mean bath in many languages. Also, many Russian words replace "b" sound with "v" sound.
Under 'svømt' it has the English translation as 'swum'. Maybe being a Northerner has altered my dialect but isn't it 'swam', as in the past tense of swimming?
The past participle form of swim is had swum. Simple past tense is swam.
We swam yesterday. We were swimming.
We had swum in the lake. We had been swimming.
English—with it's many usages and variations—is so much fun. :0)
Takk for forklaringen!