(of talk, behaviour, work etc) causing a person to lose interest and feel tired

uninteresting

belonging to, used by, coming from, done by, affecting, all or nearly all members of a group or society

average, ordinary

level; regular, steady; (of amount, distances, values) equal; (of a number) that can be divided by two

flat, uniform

dull because too ordinary

boring, uneventful

(uninteresting because) unchanging, without variety

all the same, remaining the same

an informal meeting of friends to sing songs together

all the same, remaining the same

staying, having stayed, the same

unaltered

ordinary; with no surprises

monotonous, dull