English Reference
verb · noun · adjective

swell

v. · n. · adj.
US /ˈswɛɫ/ UK /swˈɛl/ swell UK spelling swelled, swells

infinitive swell past swelled past participle swollen / swelled

  1. 01 B2 Upper Intermediate Medicine

    v.to become larger or rounder than usual, often because of an injury or liquid.

    v.to expand in volume or size, typically due to internal pressure, inflammation, or the accumulation of fluid.

    Simple

    His ankle started to swell immediately after he tripped on the stairs.

    In context

    The wood in the door frame began to swell during the humid summer months, making it nearly impossible to close properly.

    expanddistendbloat
  2. 02 C1 Advanced Formal Music

    v.to gradually become louder or stronger.

    v.to increase gradually in volume, intensity, or force.

    Simple

    The sound of the drums began to swell as the parade moved closer.

    In context

    The orchestral arrangement allowed the brass section to swell during the finale, creating a powerful emotional climax.

    crescendointensify
  3. 03 C2 Proficiency ArchaicInformal

    n.a person who is very fashionable or has a high social position.

    n.a person of high social standing or one who is dressed in an elegantly fashionable manner.

    Simple

    The hotel lobby was filled with swells in expensive suits.

    In context

    The local club was once the exclusive haunt of city swells and their debutante daughters.

  4. 04 B2 Upper Intermediate American EnglishInformalArchaic

    adj.very good or pleasant.

    adj.excellent or first-rate; used as a general term of approval.

    Simple

    We had a swell time at the party last night.

    In context

    He thought it was a swell idea to drive across the country, though his parents were less enthusiastic.

    Teacher's tip

    This usage is very old-fashioned and mostly associated with mid-20th-century American English; modern speakers use it ironically or in period dramas.

Since Wednesday, Kathmandu has swelled with international visitors – not tourists but people looking for their loved ones.

The Guardian· 30 Aug 2026

Etymology 1

From Middle English swellen, from Old English swellan (“to swell”), from Proto-West Germanic swellan, from Proto-Germanic swellaną (“to swell”), of unknown origin. Cognate with Saterland Frisian swälle (“to swell”), West Frisian swolle (“to swell”), Dutch zwellen (“to swell”), Low German swellen (“to swell”), German schwellen (“to swell”), Swedish svälla (“to swell”), Icelandic svella. The adjective may derive from the noun.

Etymology 2

From Middle English swelle, from the verb swellen (modern swell).

Etymology 3

From the noun "swell" (a person dressed in an elegant manner).

Etymology adapted from Wiktionary, available under CC BY-SA 4.0.

This entry
Origin gem-pro *swellaną
Level B2 · Upper Intermediate
Frequency Frequent
Updated