Webster's Revised Unabridged Dictionary · 1913

Remiss

Remiss (r?-m?s") , adjective

[Latin remissus, past participle of remittere to send back, relax. See Remit.]

Not energetic or exact in duty or business; not careful or prompt in fulfilling engagements; negligent; careless; tardy; behindhand; lagging; slack; hence, lacking earnestness or activity; languid; slow.
Thou never wast remiss, I bear thee witness. — Milton
These nervous, bold; those languid and remiss. — Roscommon
Its motion becomes more languid and remiss. — Woodward

Remiss , noun

The act of being remiss; inefficiency; failure. [Obsolete]
Remisses of laws. — Puttenham