UNNECESSARY
ADJECTIVES
1390 — UNBEHOVELY unprofitable, not useful; unnecessary → obs.
1429 — UNBEHOVEFUL unprofitable, not useful; unnecessary → obs.
1555 — SUPERVACANEOUS vainly added over and above what is essential; serving no purpose; superfluous, redundant, unnecessary, needless → obs.
NOUNS
1650 — NEED-NOT something unnecessary or superfluous → obs.
1940 — BLIVET — BLIVIT something annoying, unnecessary, or useless → US sl., orig. Aust. military usage
.M20 — BOONDOGGLE a trivial, useless, or unnecessary undertaking → N. Amer. sl.
PHRASES
1966 — NEEDS THAT LIKE A MOOSE NEEDS A HAT RACK doesn’t need it at all → Amer. sl.
VERBS
1883 — ROAST SNOW IN A FURNACE to attempt the unnecessary or absurd; to act foolishly and to no purpose → sl.
1905 — GIVE AN APPLE WHERE THERE IS AN ORCHARD to give an unnecessary present → Eng. dial. (Bk.)
.M20 — BOONDOGGLE to engage in a trivial, useless, or unnecessary undertaking → N. Amer. sl.
1974 — FOOL AROUND to do small unnecessary, idle operations → Amer. sl. (Bk.)
1975 — SANDPAPER THE ANCHOR to perform a job that need not and, in fact, cannot be performed; to do unnecessary work → US sl.
1999 — CARRY COALS TO NEWCASTLE vb. to bring things to a place where they abound; to do anything superfluous or unnecessary → (Bk.)
Lexicophilia 