An element in the word athragared “interaction” (PE17/14), also the gerund/infinitive of the verb car- “do, make” (PE17/68) and thus meaning “✱doing, making” as well. As such I would use this word for action as a general process, as opposed to a specific action for which I would use ᴺS. caur.
Sindarin
caur
noun. action, doing, making; verb
cared
noun. action, action, *doing, making
hûr
action, readiness for
(i chûr, o chûr, construct hur) (vigour, fiery spirit), pl. huir (i chuir) if there is a pl.
A neologism coined by Elaran in 2018 on the Vinyë Lambengolmor Discord Server (VLDS) derived from √KAR “do, make”, comparable to S. caun “outcry” from √KAN “cry aloud”. I would use this word for a specific (single) action, as opposed to the gerund cared “action, ✱doing, making” for the general process of action or carth “deed” for a notable or deliberate action. When referring to grammar, caur can be used as a term for a verb.