portcullis /pōrt- or pört-kulˈis/

1. A grating that can be let down to close a gateway of a castle, fortress, etc
2. A lattice (heraldry)
3. One of the pursuivants of the English College of Heralds
4. An Elizabethan silver halfpenny with a portcullis on the reverse

To obstruct, as with a portcullis

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