focussing vs focusing

focussing and focusing both are nouns.

Word	Noun	Adjective	Verb	Adverb
focussing	Yes	No	No	No
focusing	Yes	No	No	No

As nouns, focussing and focusing are synonyms defined as:

focussing and focusing: the concentration of attention or energy on something

Other synonyms of focussing include centering, centring, direction, focal point, focus.

focussing (noun)	focusing (noun)
the concentration of attention or energy on something	the act of bringing into focus
	the concentration of attention or energy on something