Purposeful means showing that you know exactly what you mean to do. A purposeful stride, purposeful and calm, look purposeful.
It describes the manner rather than the plan, which is why walking purposefully is the standard advice for looking as though you belong somewhere. It is a different word from purposely, which means on purpose.
1adjectivepurposefulShowing that you know exactly what you mean to do.
“She walked with a purposeful stride towards the manager's office.”
purposeful is a quality.
Purpose plus -ful, from Old French porpos, an intention.
Middle English
purpos
English
purpose
English, today
purposeful
Built from
From purpose + ful. purpose comes from Middle English purpos. From Middle English purpos, from Old French purposer (“to propose”) (with conjugation altered based on poser), from Latin prō- (“forth”) + pono (“place, put”), hence Latin propono. by surface analysis, pur- + pose.
Etymology from Wiktionary, CC BY-SA