This is the 3703rd most frequent Swedish word.
halkar
"Slips" or "is slipping."
Here, 'halkar' is used in its literal sense to describe the physical action of slipping due to the slippery surface.
Jag halkar på den isiga trottoaren.
I am slipping on the icy sidewalk.
In this expression, 'halkar' metaphorically indicates lagging or getting behind in progress or completion of something.
Han halkar efter i sina studier.
He is falling behind in his studies.
In this case, 'halkar' is figuratively used to depict entering or engaging in something without a planned or deliberate approach, giving a sense of inadvertence.