A distinguishing feature of a person or thing.
For a given field or ring, a natural number that is either the smallest positive number n such that n instances of the multiplicative identity (1) summed together yield the additive identity (0) or, if no such number exists, the number 0.
The integer part of a logarithm.
The distinguishing features of a navigational light on a lighthouse etc by which it can be identified (colour, pattern of flashes etc.).
Being a distinguishing feature of a person or thing.
One among many similar or related, yet still distinct things.
The narrow plane surface between flutings of a column; a fillet.
One member of a compound eye, as found in insects and crustaceans.
A smooth circumscribed surface.
One of a series of things, such as steps in a project.
Any one of the flat surfaces cut into a gem.
A face of codimension 1 of a polytope.
A criterion that can be used to sort and filter, such as the colour or size of products in an online store.
Any of the small joints at each segment of the spine that provide stability and help guide motion
To cut a facet into a gemstone.