Very unlucky; ill-fated. / Devoid of talent or skill.

(uncountable) The chance or random quality of an event or circumstance. / (countable) A chance or random event or circumstance.

(genetics) Having a single set of unpaired chromosomes.

A cell which is haploid. / An organism, such as a fungus, with haploid cells.

In a happy or cheerful manner; with happiness. / By good chance; fortunately, successfully. / With good will; in all happiness; willingly. / (archaic) By chance; perhaps.

(US, Canada) The greeting said near the holiday Thanksgiving.

(informal) A person who practises happy slapping.

(informal) An instance of happy slapping.

carefree or untroubled

One who is happy-go-lucky. / (obsolete) A person who does odd jobs.