Variable stars can brighten and fade in a regular pattern. A few reasons for this occurrence are shrinking and expansion, or the star's light being eclipsed by a companion object.
A short-period variable star.
Crystalline
A crystal.
That's kind of vague, but I'm thinking you mean a crystal.
A checked shirt
A short-period variable star.
A chandelier brightens A BALLROOM AFTER A WAITER MOVES A SWITCH
More than one kind of regular polygon
Yellow is a color of many meanings. It is the warmth of the sun and the renewal we see in the first flowers of spring. Rather, yellow becomes a welcoming, happy hue that brightens our spirits.
A tessellation that uses more than one kind of regular polygon is called a semi-regular tessellation.
regular
either diet or regular either diet or regular
A regular pyramid has an equilateral triangular base
regular unleaded
It is a regular verb
Regular teeth
a regular verb.