Humdrum and Lusterless

Humdrum adjective - Causing weariness, restlessness, or lack of interest.

Lusterless and humdrum are semantically related In some cases you can use "Lusterless" instead an adjective "Humdrum".

Lusterless adjective - Lacking a surface luster or gloss.

Humdrum and lusterless are semantically related in dull topic. Sometimes you can use "Humdrum" instead an adjective "Lusterless", if it concerns topics such as unimaginative.