Cowardly means running from anything frightening. A cowardly retreat, a cowardly attack, too cowardly to say it.
It is always an insult, and it is applied more often to moral failure than to physical fear — a cowardly decision is one nobody would defend aloud. A cowardly attack is a fixed phrase for one on somebody defenceless, which reverses the usual sense entirely. Note coward, cowardice; and that cowardly is an adjective despite the -ly ending, like friendly and lively, so there is no adverb form.
1adjectivecowardlyRunning from anything frightening.
“It was cowardly of him to end the relationship by text message.”
cowardly is a quality of fearfulness.
Old French coart comes from coe, a tail, from Latin cauda — probably from an animal turning tail. Coward and the tail are the same word, which is a very old joke about running away.
Middle English
*cowardly
English, today
cowardly
From Middle English cowardly and cowardly, equivalent to coward + ly. Displaced native earg.
Etymology from Wiktionary, CC BY-SA