instanter

UK: /ɪnˈstæntə/ US: /ɪnˈstæntɚ/ ,(in stan′tər)

WordReference Random House Learner's Dictionary of American English © 2025

in•stan•ter /ɪnˈstæntɚ/   adv. 

1. immediately;
   at once.

WordReference Random House Unabridged Dictionary of American English © 2025

in•stan•ter  (in stan′tər), adv. 

1. immediately;
   at once.

• Latin: urgently, insistently, equivalent. to instan(t-) instant + -ter adverb, adverbial suffix
• 1680–90

Collins Concise English Dictionary © HarperCollins Publishers::

instanter / ɪnˈstæntə/ adverb

1. without delay; (in connection with pleading) the same day or within 24 hours

Etymology: 17th Century: from Latin: urgently, from instans instant