Open English Wordnet
Adverbs
(r)immediately, instantly, straightaway, straight off, directly, now, right away, at once, forthwith, like a shotwithout delay or hesitation; with no time intervening“he answered immediately”, “found an answer straightaway”, “an official accused of dishonesty should be suspended forthwith”, “Come here now!”
(r)promptly, right awayat once (usually modifies an undesirable occurrence)“he promptly forgot the address”