- PentateuchSynonym of Torah.
- pentachoronA four-dimensional object analogous to a tetrahedron, constructed out of five tetrahedra.
- pentacronA solid with five summits (vertices), such as a square pyramid
- pentapodyA measure, verse, or series consisting of five feet.
- pentennialSynonym of quinquennial: occurring every five years.
- pentupleSynonym of quintuple in its various senses.
- peta-In the metric system, multiplying the unit to which it is attached by 10¹⁵ (a short scale quadrillion or long scale billiard). Symbol: P