a low-lying wetland / a valley

(historical) in the old timekeeping system, the period of roughly 2:00 until 4:00, both AM and PM / (by extension) a snack at eaten at around 3:00 pm / (more generally) a snack between meals

(onomatopoeia, informal) flowing thickly

(Kansai) how

(Kansai) what kind

The hiragana syllable ど𛅒 (dwo). Its equivalent in katakana is ド𛅦 (dwo).

a doss-house, cheap lodging, a flophouse, especially in a skid row area or slum / a hangout or meeting place for criminal gangs

secret base (of the military, of children, etc.)

secret society

secret police