As verbs the difference between gacked and nacked
is that gacked is past tense of gack while nacked is past tense of nack.
gacked
English
Verb
(head)
(gack)
gack
English
Interjection
(
en interjection)
(often, repeated several times) The sound of a cat coughing up a hairball.
Also used of similar noises, particularly one made to show disgust or disapproval.
Verb
(
en verb)
To make a 'gack' noise.
To expectorate a hairball.
nacked
English
Verb
(head)
(nack)
nack
English
Verb
(
en verb)
(computing) To acknowledge negatively; to send a NAK signal to.