immediately

adverb

1 it was necessary to make a decision immediately:

straight away, at once, right away, right now, instantly, now, directly, promptly, forthwith, this/that (very) minute, this/that instant, there and then, here and now, in a flash, without delay, without hesitation, without further ado, posthaste;

quickly, as fast as possible, fast, speedily, with all speed, as soon as possible, ASAP;

French tout de suite;

informal before you can say Jack Robinson, pronto, double quick, in double quick time, p.d.q. (pretty damn quick), toot sweet;

Indian, informal ekdam;

archaic straightway, instanter, forthright.

2 I sat immediately behind him:

directly, right, exactly, precisely, squarely, just, dead;

close, closely, at close quarters;

informal slap bang;

North American, informal smack dab.