As a verb rarefy
is to make rare, thin, porous, or less dense.
As an adverb rarely is
not occurring at a regular interval; seldom; not often.
To make rare, thin, porous, or less dense
To expand or enlarge without adding any new portion of matter to.
Not occurring at a regular interval; seldom; not often.
- We rarely go to the theatre.
Unusually well; excellently.
To a rare degree; very.
- Rarely do you ever find an eagle this far up the river.
- others speake very honourably of his life and death, and in all other circumstances declare him to have beene a most excellent and rarely virtuous man.
It is grammatically a negative word. It therefore collocates with ever rather than never.
* Compare We rarely ever go to the theatre.'' with ''We almost never go to the theatre.
* once in a while
* frequently, usually, often