The term 'in a sluggish way' can be described using three different words: leadenly (8 letters), inertly (7 letters) and LAZILY (6 letters). Leadenly is an adjective that means 'heavy or oppressive in a way that makes movement or activity difficult'. Inertly is an adjective that means 'lacking the ability or strength to move or act'. Lastly, LAZILY is an adjective that means 'not showing much effort or energy'. All three words describe something that is done in a slow, sluggish manner.