(n.) Plural of Activity.

act acting action actions activism activities acts actuation address affair affairs affectation air animation ardor artificial radioactivity bag bearing behavior behavior pattern behavioral norm behavioral science brio briskness business bustle campaign carriage cause commerce commitment comportment concern concernment conduct contamination crusade culture pattern curiage custom decontamination demeanor deportment doing doings drive dynamics elan employ employment endeavor energy enterprise enthusiasm exercise exercising exertion faith fallout folkway function functioning gestures glow going goings-on great cause guise gusto half-life impetuosity impetus interest issue job joie de vivre kinematics kinesipathy kinesis kinesitherapy kinetics labor life lifework liveliness lookout lustiness maintien manner manners mass movement matter method methodology methods mettle mien mobilization modus vivendi motion motions motivation move movement movements moves moving natural radioactivity nuclear radiation observable behavior occupation operation operations pattern perkiness pertness play poise port pose posture practice praxis presence principle procedure proceeding project pursuit radiant energy radiation radioactive radiation radioactivity radiocarbon dating radiolucency radiopacity radiosensibility radiosensitivity reason for being restlessness robustness running saturation point service social science specific activity spirit spiritedness stir stirring style swing tactics thing tone undertaking unrest velocity venture vigor vim vivacity vocation warmth way way of life ways work working workings zest zestfulness