infliction vs pain in the neck

infliction and pain in the neck both are nouns.

Word	Noun	Adjective	Verb	Adverb
infliction	Yes	No	No	No
pain in the neck	Yes	No	No	No

As nouns, infliction and pain in the neck are synonyms defined as:

infliction and pain in the neck: something or someone that causes trouble; a source of unhappiness

Other synonyms of infliction include annoyance, bother, botheration, nuisance, pain, pain in the ass.

infliction (noun)	pain in the neck (noun)
the act of imposing something (as a tax or an embargo)	something or someone that causes trouble; a source of unhappiness
an act causing pain or damage
something or someone that causes trouble; a source of unhappiness