in two shakes
• very quickly.
• "I'll be back to you in two shakes"
Similar:
in a moment,
in a second,
in a flash,
in a minute,
shortly,
any minute,
any minute now,
in a short time,
(very) soon,
in an instant,
in the twinkling of an eye,
in (less than) no time,
in no time at all,
before you know it,
before long,
momentarily,
in a jiffy,
in the blink of an eye,
in a blink,
in the wink of an eye,
in a wink,
before you can say knife,
in a tick,
in two ticks,
in a mo,
in a snap,