There isn't really an opposite. Some might claim a mammal is the opposite of a reptile, but this comparison breaks down when you look at their Biology in detail.
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Yes applying the concept of an opposite to living things is a bit meaningless.
reptile
reptile
what is opposite meaning of lucid
A dinosaur was a prehistoric lizard.Dinosaur was a reptile. The word Dinosaur, derived from the Greek word "deinos", meaning "marvelous" or "terrible", and "sauros", meaning "lizard".
mindedness...........
the opposite meaning is to be rememberd or known not to be forgotten
The opposite meaning of unceasing is ceasing, or, to cease. &:-)
Another word for "opposite meaning" is an "antonym." For example, the opposite of fat is thin. The opposite of rich is poor. The opposite of up is down.
The opposite of lass is lad, which refers to a young boy or man.
There is no antonym for the word avenge, although there is an opposite for the meaning. The meaning is revenge, so the opposite meaning would be forgiveness.
A mammal has fur, is warm blooded, and usually gives live birth. Therefore, in most ways they are not alike. That could be considered opposite.
There are several possible words:For useless meaning valueless, the opposite could be "treasured."For useless meaning not workable, the opposite could be "effective."For useless meaning not required, the opposite could be "necessary."For useless meaning worthless, the opposite could be "practical."For useless meaning inappropriate, the opposite could be "pertinent."For useless meaning unhelpful, the opposite could be "desirable."useful - look it up in a dicitonary and you'll see a picture of me.