Webster's Revised Unabridged Dictionary · 1913

Padlock

Padlock , noun

[Perh. orig., a lock for a pad gate, or a gate opening to a path, or perh., a lock for a basket or pannier, and from Prov. English pad a pannier. Compare Pad a path, Paddler.]

1.
A portable lock with a bow which is usually jointed or pivoted at one end so that it can be opened, the other end being fastened by the bolt, -- used for fastening by passing the bow through a staple over a hasp or through the links of a chain, etc.
2.
A curb; a restraint. [Figurative:]

Padlock , transitive verb

To fasten with, or as with, a padlock; to stop; to shut; to confine as by a padlock. — Milton. Tennyson