manly (adj.)

c. 1200, "human; characteristic of human beings," also "possessing virtues proper to a male person" (resoluteness, independence, steadfastness, reliability); from man (n.) + -ly (1). Meaning "masculine, not boyish or womanish, proper to fighting men" is attested from late 14c. Old English had werlic "male, masculine, manly."

Manly, matching womanly, is the word into which have been gathered the highest conceptions of what is noble in man or worthy of his manhood, especially as opposed to which is fawning or underhand. Manful expresses the stanchness, fearlessness, and energy of a man, as opposed to that which is weak, cowardly, or supine. [Century Dictionary, 1895]

updated on November 28, 2018

Definitions of manly from WordNet
manly (adj.)
possessing qualities befitting a man;
Synonyms: manful / manlike
manly (adj.)
characteristic of a man;
manly sports
Synonyms: male / manful / manlike / virile
manly (adv.)
in a manful manner; with qualities thought to befit a man;
Synonyms: manfully
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