When something is dreary it's depressing or lifeless in a rainy-day way. I finished my work, there was nothing on TV, and the rain just wouldn't stop: what a dreary day!

Dreary can refer to a feeling, a place, a time, or even a thing. It sounds a little like a combination of "drizzle" and "teary," and that's not a bad way to remember what it means. My grandmother's house was a dreary affair: run down, poorly lit, and silent but for the buzz of the florescent light in the cramped kitchen. Some might call the recession a depression: I call it dreary, either way. If the economy remains dreary like this much longer, I just might move to China.

Definitions of dreary

adj lacking in liveliness or charm or surprise

“a series of dreary dinner parties”
lacking in liveliness or animation

adj causing dejection

blue, dark, dingy, disconsolate, dismal, drab, drear, gloomy, grim, sorry
cheerless, depressing, uncheerful
causing sad feelings of gloom and inadequacy