Frequency: The word is one of the 3000 most common words in English.
1.
Fairly means to quite a large degree. For example, if you say that something is fairly old, you mean that it is old but not very old.
Both ships are fairly new...
We did fairly well but only fairly well.
= quite
ADV: ADV adj/adv
2.
You use fairly instead of 'very' to add emphasis to an adjective or adverb without making it sound too forceful.
Were you always fairly bright at school?...
I'll have no income and no home and will need a job fairly badly.
= pretty
ADV: ADV adj/adv [vagueness]
3.