Blessed, a.
1. Hallowed; consecrated; worthy of blessing or adoration; heavenly; holy. O, run; prevent them with thy humble ode, And lay it lowly at his blessed feet. Milton.
2. Enjoying happiness or bliss; favored with blessings; happy; highly favored. All generations shall call me blessed. Luke i. 48. Towards England's blessed shore. Shak.
3. Imparting happiness or bliss; fraught with happiness; blissful; joyful. "Then was a blessed time." "So blessed a disposition." Shak.
4. Enjoying, or pertaining to, spiritual happiness, or heavenly felicity; as, the blessed in heaven. Reverenced like a blessed saint. Shak. Cast out from God and blessed vision. Milton.
3 more senses
5. (R. C. Ch.)
Beatified.
6. Used euphemistically, ironically, or intensively. Not a blessed man came to set her [a boat] free. R. D. Blackmore.
Shades of meaning
Fernald has no entry of its own for blessed; he lists it under happy, holy.
Where he writes about it:
In this sense happy is closely allied to fortunate and lucky. (See fortunate.) Happy has, however, so far diverged from this original sense as to apply to advantages where chance is not recognized, or is even excluded by direct reference to the divine will, when it becomes almost equivalent to blessed. — from happy