Similar words
quellen
quellen and schwellen are close synonyms for "to swell"; quellen also has a "to well up," like a liquid emerging, sense.
Similar in other languages
Portuguese
avolumar
avolumar is the Portuguese word for the same thing — both mean "to swell."
Portuguese
inchar
inchar is the Portuguese word for the same thing — both mean "to swell."
Practice
1 What does schwellen mean?
to swell
2 Fill the gap: Ihr Knöchel ___ nach dem Sturz an.
Full sentence: Ihr Knöchel schwoll nach dem Sturz an. (Her ankle swelled after the fall.)
3 Which fingerprint chart matches schwellen?
schwellen: neutral register, common frequency, general domain, neutral connotation.