IPA: /ˈswɪmɪŋli/
KK: /ˈswɪmɪŋli/
In a manner that is very successful or easy; smoothly and without problems.
The project is progressing swimmingly, and we expect to finish ahead of schedule.
Swimmingly → It is formed from "swim" (from Old English *swimman*, meaning to move through water) and the adverbial suffix "-ly" (meaning in a manner of). The word "swimmingly" means in a manner that is smooth and effortless, like swimming through water.
Think of moving smoothly through water ('swim') and doing it 'in a manner' ('-ly') that feels effortless. This helps you remember that 'swimmingly' means something is going very smoothly.