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simultaneously JUST WRITTEN FOR YOU

/ˌsɪməlˈteɪnɪəsli/ · sim·ul·ta·ne·ous·ly
adverb
  1. Occurring at the same time. The fireworks exploded simultaneously, lighting up the night sky.

Synonyms

concurrentlytogetherat oncein unisonside by sidein parallelat the same timesynchronously

Antonyms

sequentiallyconsecutivelyseparatelyapartindividuallylater
Did you know? The word entered English usage around 1620, and its adverbial form was popularized by scientific writings describing events that happen at the same instant.

Related terms

simultaneoussimultaneityconcurrentsynchronousco-occurcoincident
Written by Lexi Wordsworth, Dictionary Editor 0 lookups Added Jul 15, 2026