A small passerine bird (Phoenicurus phoenicurus).

The nightingale, Luscinia megarhynchos.

That which is known by most people, and thus cannot reasonably be contested.

The herb Eupatorium perfoliatum, also known as thoroughwort. Often used by herbalists as a stimulant, febrifuge, and laxative.

A small falcon, Falco tinnunculus.

Alternative form of commonsensical

A small bird, the Eurasian bullfinch (Pyrrhula pyrrhula).

Carpinus betulus; a deciduous tree with hard wood, native to many parts of Europe.

Phoca vitulina, a seal living in the northern Atlantic and Pacific oceans.

(mathematics) Any integer that is a common multiple of the denominators of two or more fractions. / (by extension, figuratively) A trait or attribute that is shared by all members of some category.