Not focused straight at the target or subject, but by more subtle means
Not of obvious or immediate cause, but as a secondary result
Not involving the quickest, shortest, or most convenient path
An indirect cost.
An indirect radiator
To access by means of indirection; to dereference.
Secret; surreptitious.
Done by moving the hand (and arm) from below.
Sly, dishonest, corrupt, cheating.
Insincere; sarcastic.
An underhanded compliment is actually criticism.
His underhanded trick backfired and he was disqualified.
Understaffed.
Devious people, collectively.
In an underhanded manner.