Keyword Analysis & Research: what does fn mean in green fn

Keyword Analysis

Keyword	CPC	PCC	Volume	Score	Length of keyword
what does fn mean in green fn	1.06	0.1	9680	100	29
what	1.62	0.3	1388	9	4
does	1.54	0.2	6285	58	4
fn	0.85	0.7	5830	98	2
mean	0.44	1	4279	46	4
in	0.36	0.7	9734	77	2
green	1.76	0.2	8550	32	5
fn	0.63	0.9	5220	85	2

Keyword	CPC	PCC	Volume	Score
what does fn mean in green fn	1.96	0.8	4390	20