mis·reck·on 
(mĭs-rĕkən)
(mĭs-rĕkən)v. mis·reck·oned, mis·reck·on·ing, mis·reck·ons
v.tr.
To reckon incorrectly; miscalculate.
v.intr.
To engage in incorrect reckoning or miscalculation.
mis·reckon·ing n.
- Proteus
- prothalamion
- prothallial
- prothallium
- prothallus
- prothesis
- prothetic
- prothetically
- prothonotarial
- prothonotary
- prothonotary apostolic
- prothonotary apostolic
- prothonotary warbler
- prothoracic
- prothoracic gland
- prothorax
- prothrombin
- protist
- protistan
- protistology
- protium
- proto-
- Proto-Algonquian
- protoceratops
- protocol