Definition of laugh:
(n) :
an expression of
mirth particular to the human
species; the sound heard in laughing;
laughter; something that provokes mirth or scorn
"1803 The Poetical Works of Oliver Goldsmith, M.B.: With an Account of His Life Page 45: And the loud laugh that spoke the vacant mind. -- Oliver Goldsmith"
(v) :
to show
mirth,
satisfaction, or
derision, by
peculiar movement of the
muscles of the
face, particularly of the
mouth, causing a
lighting up of the face and
eyes, and usually accompanied by the
emission of
explosive or
chuckling sounds from the
chest and
throat; to
indulge in
laughter; to be or appear cheerful, pleasant, mirthful, lively, or brilliant; to sparkle; to sport
"queen Hecuba laughed that her eyes ran o'er. -- Shakespeare, Troilus and Cressida, I-ii"