Here is a list of nouns that start with APP.
appanage, apparel, apparency, apparition, appeal
appearance, appeasement, appestat, appetite, applause
apple, applejack, appliance, applicability, applicant
application, applicator, appointee, appointment, apportionment
appraisal, appreciation, apprehension, apprentice, apprenticeship
approach, appropriation, approval, approximation
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