sweltering

UK: /ˈswɛltərɪŋ/ US: /ˈswɛltərɪŋ/ ,(swel′tər ing)

WordReference Random House Learner's Dictionary of American English © 2026

swel•ter•ing /ˈswɛltərɪŋ/   adj. 

1. suffering from too much heat:
   The sweltering students could hardly keep their minds on their lessons.
2. showing or having too much heat:
   a sweltering classroom.

WordReference Random House Unabridged Dictionary of American English © 2026

swel•ter•ing  (swel′tər ing), adj. 

1. suffering oppressive heat.
2. characterized by oppressive heat;
   sultry.

• swelter + -ing² 1565–75

swel′ter•ing•ly, adv. 

Collins Concise English Dictionary © HarperCollins Publishers::

sweltering / ˈswɛltərɪŋ/ adjective

1. oppressively hot and humid: a sweltering day
   Also (archaic): sweltry

ˈswelteringly adverb

WordReference Random House Learner's Dictionary of American English © 2026

swel•ter /ˈswɛltɚ/   v. [no object]

1. to suffer from too much heat:
   We sweltered throughout the summer.

n. [countable]

2. a sweltering condition.

WordReference Random House Unabridged Dictionary of American English © 2026

swel•ter  (swel′tər), v.i. 

1. to suffer from oppressive heat.

v.t. 

2. to oppress with heat.
3. [Archaic.] to exude, as venom.

n. 

4. a sweltering condition.

• 1375–1425; late Middle English swelt(e)ren (verb, verbal), equivalent. to swelt(en) to be overcome with heat (Old English sweltan to die; cognate with Old Norse svelta, Gothic swiltan) + -eren -er⁶

Collins Concise English Dictionary © HarperCollins Publishers::

swelter / ˈswɛltə/ verb

1. (intransitive) to suffer under oppressive heat, esp to sweat and feel faint
2. (transitive) to cause to suffer under oppressive heat

noun

1. a sweltering condition (esp in the phrase in a swelter)
2. oppressive humid heat

Etymology: 15th Century swelten, from Old English sweltan to die; related to Old Norse svelta to starve, Old High German swelzan to burn with passion; see sultry