Alacritous

Part of speech: adjective

Definitions

1. Showing eager willingness and speed in action or response with enthusiastic promptness
2. Characterized by brisk enthusiasm and prompt readiness to act or respond without hesitation
3. Demonstrating keen eagerness combined with swift and willing execution of tasks or duties

Etymology: Alacritous is simply alacrity with the suffix "-ous" attached, meaning "full of alacrity." The noun it grows from has a more dramatic past than the adjective: "alacrity" comes from the Latin "alacritas," which meant liveliness or cheerful eagerness, and it was built on "alacer," a word for lively or brisk. Those Latin roots carry the sense of quick, spirited readiness that the English word still keeps. The "-ous" ending is a familiar English adjective-maker, found in words like "famous" and "joyous," that turns a noun into a description of someone or something having that quality. So an alacritous response is one that is full of the eagerness and promptness that "alacrity" names.