What is another word for sluggish?

Here are some words that can be used as synonyms for "sluggish," depending on the context:

General synonyms:

* Slow

* Letharargic

* Drowsy

* Inactive

* Languid

* Tired

* Listless

* Heavy

* Unresponsive

* Dull

More specific synonyms:

* For a person: Weary, exhausted, apathetic, indifferent, unmotivated, lazy

* For a machine: Lagging, lagging behind, underperforming, malfunctioning

* For a business: Stagnant, stagnant economy, flat, slow growth, weak

* For a flow (e.g., of traffic): Congested, jammed, backed up, gridlocked

The best word to use will depend on the specific situation and the nuance you want to convey.