the world > movement > impact > impinge upon [verb (transitive)] > cause to impinge > gently or lightly (3)
To strike (the foot, hand, etc.) lightly upon something.
To strike or cause to strike (usually with something soft and of broadish surface) so as to exert a… the brush, dabber, etc. used.
To dash down heavily or with some force; also, †to knock (gently). Now dialect.