The word "observable" means something that can be seen, noticed, or detected with the human senses or with instruments. It refers to things that are able to be observed or perceived. Full definition
Ultimately, as he states, the God creative enough «to make the entire observable universe in a dense dot of pure energy is incomprehensible, beyond human imagining,» but still «we can see the consequences of this unimaginably powerful creative act: a universe congenial to the ultimate formation of life, life giving rise to intelligence that can ask questions science can not answer. (firstthings.com)
The theory of evolution by natural selection is a beautiful explanation for the diversity of life based on observable facts. (religion.blogs.cnn.com)
If the diagnostics come up positive for blast - related brain trauma, the neurosurgeon takes action based on observable signs of trauma. (discovermagazine.com)