(obsolete, rare) One dressed in black; a mourner

plural of atrate

(pharmacology) A muscle relaxant administered intravenously in the form of its besylate C₆₅H₈₂N₂O₁₈S₂ especially in conjunction with general anesthesia to facilitate insertion of an endotracheal tube or to relax skeletal muscles during surgery or mechanical ventilation. It counteracts the action of the neurotransmitter acetylcholine at neuromuscular junctions by binding to the same receptors it acts upon.

A drug being researched for the treatment of various cancers.

(organic chemistry) Any of a class of tricyclic cagelike heterocycles having a transannular dative bond between a nitrogen and another heteroatom

(obsolete) melancholy; atrabilious

(obsolete) Like ink; suitable for making ink.

(transitive, now chiefly dialectal) To vex; trouble; frighten; torment; harass.

(medicine, obsolete) Of or relating to black bile. / Melancholic or hypochondriac; atrabilious.

(zoology) Any snake in the family Atractaspididae.