in music, "resembling or of the style of the blues," 1946, from blues (n.1) + -y (2).
Entries linking to bluesy
blues n.1
"music form featuring flatted thirds and sevenths," possibly c. 1895 (though officially 1912, in W.C. Handy's "Memphis Blues"). Blue note "minor interval where a major would be expected" is attested from 1919, and at first was suspected as a source of the term. Also compare blues (n.2).
I am under the impression that these terms [blue note, blue chord] were contemporary with, if they did not precede and foreshadow, the period of our innumerable musical 'Blues.' What the uninitiated tried to define by that homely appellation was, perhaps, an indistinct association of the minor mode and dyspeptic intonation with poor digestion; in reality, it is the advent in popular music of something which the textbooks call ambiguous chords, altered notes, extraneous modulation, and deceptive cadence. [Carl Engel, "Jazz: A Musical Discussion," The Atlantic Monthly, August 1922]
-y 2
adjective suffix, "full of or characterized by," from Old English -ig, from Proto-Germanic *-iga- (source also of Dutch, Danish, German -ig, Gothic -egs), from PIE -(i)ko-, adjectival suffix, cognate with elements in Greek -ikos, Latin -icus (see -ic). Originally added to nouns in Old English; used from 13c. with verbs, and by 15c. even with other adjectives (for example crispy). Adjectives such as hugy, vasty are artificial words that exist for the sake of poetical metrics.