practical: Do not confound with practicable. The former means "that can be put into practise or rendered applicable for use; as, practical knowledge"; whereas the latter is perhaps best expressed by the synonym "feasible." Practical has a general application, being governed by actual use and experience; as, practical statesmanship or wisdom: practicable, on the contrary, is particular, and signifies the suitability of the particular thing named to the desired end. Thus one may know a practical man but not a practicable one.
pray, prey: Exercise care in using these homophones. Etymologically they are distinct. Pray is from Old French praier, to ask; while prey is from Old French preier, booty, probably from the Latin prœhendo, to seize. Note the difference in spelling.
precedent, president: Although almost homophones these terms have widely different meanings. A precedent is something that has occurred before in time and is considered as an established rule or an authorized example; a president is the head of a nation, society, or the like.
predicate, predict: Though these words are both derived from the same Latin source, the one must not be used for the other. To predict is to foretell, whereas to predicate is to proclaim as inherent. In United States usage predicate, with on or upon, is