The fundamental, simple meaning of the phrase "hold up" is "keep in upper position" or close derivative meanings: "keep it active", "keep it running", especially in situation when it would stop/drop by itself without holding.

Unfortunately, due to it being a phrasal verb with a truly impressive list of meanings, using hold up in its simple meaning becomes awfully ambiguous, especially if there's no context to qualify the meaning.

In particular, I need to name a hold-up time, the time during which a signal remains active after its normal activation source is gone, and not have it confusable with the meaning of hold up as something that prevents start. Can you help me find a neat synonym for such a meaning?

  • Could you give an example sentence of how you'd like to use these words? Jul 10, 2012 at 13:38
  • Something like "I use a belt to _______ my trousers"?
    – Ste
    Jul 10, 2012 at 13:47
  • @Frustrated: the module tunes the readout parameters (...) applying signal postprocessing (negation, delay and hold-up times), counting impulses and sending processed data. But Ste's example is fine too (although the context is much clearer).
    – SF.
    Jul 10, 2012 at 13:56
  • I think you should stick with hold-up time. Then create a glossary entry and say: The time for which the output signal is held high after removal of the signal activation stimulus. ... or something like that. Alternatively if you have modeled this delay as a first order lag you can refer to its time constant, tau.
    – Jim
    Jul 10, 2012 at 19:05

6 Answers 6


You can call it the "stretch time". The term "stretch" is commonly used to indicate the time added to a signal's active state to ensure that a brief signal isn't missed by a detector that requires a minimum signal length. The word "stretch" clearly connotes the concept of added length. Devices that do just this are often called "pulse stretchers".


The output pulse, shown at FIG. 3F, from the multivibrator 28 is fed to another monostable multivibrator 30. Multivibrators 26 and 28 are triggered by the leading edge of the output pulse 3D from the Schmitt trigger 24 and, moreover, the length, or duration of the output pulse (FIG. 3E) from multivibrator 26 is adjusted so as to be longer than the input pulse 3C. The pulse of FIG. 3E sets the stretch time for the input pulse of FIG. 3C. The monostable multivibrator 28 sets the time for the triggering of the multivibrator 30 and the latter multivibrator provides an output pulse having the general shape shown in FIG. 3G. -- US Patent 3,681,601


A positive pulse g will appear at the output of comparator 8 whenever the negative pulse associated with a QRS wave crosses the threshold f. The output of comparator 8 is applied to a stretch circuit 9 in which a capacitor is rapidly charged to a fixed voltage during each pulse g and allowed to discharge only after the end of each such pulse. When the capacitor is so charged a positive "Blanking pulse" h appears at the output of the stretch circuit comparator and remains present until the capacitor has discharged from the above fixed voltage to some pre-set lower voltage. The stretch circuit operates so as to extend each pulse g by a fixed time** so chosen that the Blanking pulse duration exceeds the duration of the QRS wave initiating it by, for example 150 msec. -- US Patent 3,654,916


From your description of what you intend, perhaps you want something like "persistence time"- which should convey that something remains active despite conditions (in your case, the absence of the activation source). For further clarification, "signal persistence time" might remove any further ambiguity depending on the context.


The notion of residue might work: Residual light, residual power, residual energy, residual signal.

  • doesn't that imply the signal remains in this state all by itself, instead of being actively kept in given state?
    – SF.
    Jul 10, 2012 at 19:43

I like dorchard's persist and also offer endure:

: to continue in the same state

So you could call it endurance time.

  • This would be fine if it worked for negative state just the same. Thing is, it's about keeping the positive output prolonged (falling slope delayed) while not affecting the rising slope.
    – SF.
    Jul 10, 2012 at 19:04

...the time during which a signal remains active after its normal activation source is gone

This could be called the die-off time since you are referring to the time between the removal of the signal source and when the signal is not longer detectable.

  • Not exactly that. It's a binary signal from a sensor. The sensor can produce short-lived false negatives. By prolonging the signal we prevent them and keep the signal steady for as long as the event occurs (plus a tiny extra).
    – SF.
    Jul 10, 2012 at 19:02
  • @SF.: Hmm... could you call it "signal-extension time"? Jul 10, 2012 at 19:19

If I understand correctly, you're looking to describe the amount of time it takes the signal to drop below a certain threshold after it's sustain has ended. I believe it would not be incorrect to call that decay time, as that is commonly used in musical and electronic applications.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.