Proform Crosswalk 425 Treadmill

crosswalk
crossing: a path (often marked) where something (as a street or railroad) can be crossed to get from one side to the other
A marked part of a road where pedestrians have right of way to cross
A pedestrian crossing or crosswalk is a designated point on a road at which some means are employed to assist pedestrians wishing to cross.
A crosswalk is a table that shows equivalent elements (or "fields") in more than one database. It maps the elements in one metadata scheme to the equivalent elements in another scheme.

treadmill
an exercise device consisting of an endless belt on which a person can walk or jog without changing place
a mill that is powered by men or animals walking on a circular belt or climbing steps
An exercise machine, typically with a continuous belt, that allows one to walk or run in place
A job or situation that is tiring, boring, or unpleasant and from which it is hard to escape
A device formerly used for driving machinery, consisting of a large wheel with steps fitted into its inner surface. It was turned by the weight of people or animals treading the steps
a job involving drudgery and confinement

proform
A proform is an expression (typically a word) which has no specific content of its own, but which derives its content from its antecedent.
a form representing another constituent. Pronouns are common proforms, e.g. My little sister saw herself in the mirror.
A pro-form is a type of function word or expression that stands in for (expresses the same content as) another word, phrase, clause or sentence where the meaning is recoverable from the context.

425
400 (four hundred) is the natural number following 399 and preceding 401. (For the year 400 AD, see 400)
* October 23—Valentinian III becomes Western Roman Emperor. * Aetius leads an army into Italy to support the self-proclaimed emperor Joannes. * Galla Placidia becomes a regent for her son.