Immediately.
Synonyms:
| at once, | instanter, | presently, | straightway, |
| directly, | instantly, | right away, | this instant, |
| forthwith, | now, | right off, | without delay. |
The strong and general human tendency to procrastination is shown in the progressive weakening of the various words in this group. Immediately primarily signifies without the intervention of anything as a medium, hence without the intervention of any, even the briefest, interval or lapse of time. By and by, which was once a synonym, has become an antonym of immediately, meaning at some (perhaps remote) future time. Directly, which once meant with no intervening time, now means after some little while; presently no longer means in this very present, but before very long. Even immediately is sliding from its instantaneousness, so that we are fain to substitute at once, instantly, etc., when we would make promptness emphatic. Right away and right off are vigorous conversational expressions in the United States.
Antonyms:
after a while, by and by, hereafter, in the future, some time.