lifeless adj.
1 dead
VERBS appear, be, lie, look She lay lifeless in the snow.
ADV. completely | almost, nearly His body was limp and almost lifeless. | apparently, seemingly She lay there, apparently lifeless.
2 without living things
VERBS be
ADV. completely a time when they earth was completely lifeless
3 dull/without interest
VERBS be, seem | become
ADV. completely | rather The acting was dull and rather lifeless.
You can also check other dicts: lifeless (English, 中文解释 ), wordnet sense, Collins Definition