So-called fallen angels differ from junk bonds in that

junk bonds refer to newly issued bonds with low credit ratings, whereas fallen angels refer to previously issued bonds which have had their credit ratings fall below investment grade.

junk bonds refer to previously issued bonds which have had their credit ratings fall below Baa, whereas fallen angels refer to newly issued bonds with low credit ratings.

junk bonds have ratings below Baa, whereas fallen angels have ratings below C.

fallen angels have ratings below Baa, whereas junk bonds have ratings below C.