A harmonica is a small musical instrument. You play the harmonica by moving it across your lips and blowing and sucking air through it.
harmonica in British English
(hɑːˈmɒnɪkə)
noun
1. Also called: mouth organ
a small wind instrument of the reed organ family in which reeds of graduated lengths set into a metal plate enclosed in a narrow oblong box are made to vibrate by blowing and sucking
2. glass harmonica
Word origin
C18: from Latin harmonicus relating to harmony
harmonica in American English
(hɑrˈmɑnɪkə)
US
noun
1.
a small wind instrument played with the mouth; mouth organ: it has a series of graduated metal reeds that vibrate and produce tones when air is blown or sucked across them
2.
glass harmonica
Word origin
L, fem. of harmonicus (see harmonic): name altered < earlier armonica (< It, fem. of armonico, of same orig.) by Franklin2, who developed this instrument from an earlier form