vexation vs headache

vexation and headache both are nouns.

Word	Noun	Adjective	Verb	Adverb
vexation	Yes	No	No	No
headache	Yes	No	No	No

As nouns, vexation and headache are synonyms defined as:

vexation and headache: something or someone that causes anxiety; a source of unhappiness

Other synonyms of vexation include concern, worry.

vexation (noun)	headache (noun)
the act of troubling or annoying someone	something or someone that causes anxiety; a source of unhappiness
something or someone that causes anxiety; a source of unhappiness	pain in the head caused by dilation of cerebral arteries or muscle contractions or a reaction to drugs
anger produced by some annoying irritation
the psychological state of being irritated or annoyed