vex vs mix up

vex and mix up both are verbs.

Word	Noun	Adjective	Verb	Adverb
vex	No	No	Yes	No
mix up	No	No	Yes	No

As verbs, mix up is a hyponym of vex; that is, mix up is a word with a more specific, narrower meaning than vex:

Other hyponyms of vex include stump, riddle, elude, escape.

vex (verb)	mix up (verb)
be a mystery or bewildering to	cause to be perplexed or confounded
subject to prolonged examination, discussion, or deliberation	assemble without order or sense
change the arrangement or position of
cause annoyance in; disturb, especially by minor irritations
disturb the peace of mind of; afflict with mental agitation or distress