PESKIEST
Scrabble letter values: P3E1S1K5I1E1S1T1 = 14
Definition
PESKIEST is the superlative of PESKY.
adjective PESKY: causing irritation or annoyance.
Synonyms of PESKY: annoying, bothersome, galling, irritating, nettlesome, pestering, pestiferous, plaguy