gratuitous

adjectives

without cause

"a gratuitous insult"

gratuitous

is similar to

not merited or deserved

"received an unmerited honorary degree"

costing nothing

"complimentary tickets"; "free admission"

complimentary, costless, free, gratis, gratuitous

unnecessary and unwarranted

"a strikers' tent camp...was burned with needless loss of life"