greater

The ordinary comparative, formed with -er in the regular way for short adjectives rather than with more. It compares great in its senses of size, quantity and importance: greater species diversity, greater renown, usually followed by than. Keep it apart from the fixed 'larger of two' use, which ranks one thing against its partner instead of comparing degrees and cannot itself be compared further.

A ranking label rather than a true comparison: it picks out the larger or weightier member of a pair, and its natural partner is lesser. Naturalists use the pair to tell related species apart, as in the greater yellowlegs. Because it already names the larger of two, it does not take degrees. Nothing is more greater, and it usually comes with the: the greater of the two.

The metropolitan use, set against the city proper. Edward Walford's Greater London (1883) opens by calling the term "vague and ill-defined" next to London proper, and that tension is the point. The core city has borders, while the conurbation spreads. It is usually capitalized as part of a name (Greater New York), but lowercase greater Tokyo works as a looser description of the same idea.

A word that always stands before the place it enlarges, never after it. In settled names it is capitalized and part of the name itself, as in the Greater Antilles. Written in lowercase, it marks a looser, unofficial region. A phrase like the greater Midwest gestures at a wide area without claiming fixed borders, so the capital letter tells the reader whether a boundary is official.

Here the word is applied to a whole state, not to a city and its suburbs as in the metropolitan use. It can describe a past extent neutrally, as with Greater Armenia, or name a territory someone hopes to gain. In the second case the phrase works as a political claim, so writers should make clear whether they mean historical borders or an ambition.