tedious vs irksome

tedious and irksome both are adjectives.

Word	Noun	Adjective	Verb	Adverb
tedious	No	Yes	No	No
irksome	No	Yes	No	No

As adjectives, tedious and irksome are synonyms defined as:

tedious and irksome: so lacking in interest as to cause mental weariness

Other synonyms of tedious include boring, deadening, dull, ho-hum, slow, tiresome, wearisome.

tedious (adjective)	irksome (adjective)
using or containing too many words	so lacking in interest as to cause mental weariness
so lacking in interest as to cause mental weariness