As adjectives the difference between peskiest and peakiest
is that peskiest is (pesky) while peakiest is (peaky).
peskiest
English
Adjective
(head)
(pesky)
pesky
English
Adjective
(er)
Annoying, troublesome, irritating.
Synonyms
* See also
Anagrams
*
peakiest
English
Adjective
(head)
(peaky)
peaky
English
Adjective
(er)
Sickly; peaked.
Characterised by peaks.