What words start with pent and mean five of something?

Answer 1

Almost any English compound word that begins with "pent" means five of something (some exceptions listed below). Some examples of pent meaning five include:

• Pentagon = five sides
• Pentagram/Pentacle = five corners
• Pentagon = five sides
• Pentameter = five metrical or iambic feet
• Pentad = five years
• Pentadactyl = five fingers
• Pentose = five molecules
• Pentateuch = five Books
  
• Pentium = fifth version of the 80*86 processor

Exceptions, where words beginning with pent do NOT mean five of something:

• when combined with other Greek number roots, i. e. pentadeca- = 15 of something
  
• when the root comes from Latin pentire, meaning remorse/repent, i. e. Pentecost, pentimento
• when the root comes from French apendre, meaning add-on, i. e. penthouse
• when the word comes from the US Pentagon, i. e. Pentagonese

Answer 2

pentachord, pentacle, pentad, pentadactyl, pentagon, pentagram, pentahedron, pentamer, pentameter, pentangle, pentaploid, pentaprism, pentaquark, Pentateuch, pentathlon, pentathlete, pentatonic, pentavalent

Answer 3

Pentagon, pentacle, pentagram, pentathlon