As defined by Noah Webster's original 1828 Dictionary:
HAP'PINESS, n. [from happy.] The agreeable sensations which spring from the enjoyment of good; that state of a being in which his desires are gratified, by the enjoyment of pleasure without pain; felicity; but happiness usually expresses less than felicity, and felicity less than bliss. Happiness is comparative. To a person distressed with pain, relief from that pain affords happiness; in other cases we give the name happiness to positive pleasure or an excitement of agreeable sensations. Happiness therefore admits of indefinite degrees of increase in enjoyment, or gratification of desires. Perfect happiness, or pleasure unalloyed with pain, is not attainable in this life.
HAP'PINESS, n. [from happy.] The agreeable sensations which spring from the enjoyment of good; that state of a being in which his desires are gratified, by the enjoyment of pleasure without pain; felicity; but happiness usually expresses less than felicity, and felicity less than bliss. Happiness is comparative. To a person distressed with pain, relief from that pain affords happiness; in other cases we give the name happiness to positive pleasure or an excitement of agreeable sensations. Happiness therefore admits of indefinite degrees of increase in enjoyment, or gratification of desires. Perfect happiness, or pleasure unalloyed with pain, is not attainable in this life.