instillation vs instillment

instillation and instillment both are nouns.

Word	Noun	Adjective	Verb	Adverb
instillation	Yes	No	No	No
instillment	Yes	No	No	No

As nouns, instillation and instillment are synonyms defined as:

instillation and instillment: the introduction of a liquid (by pouring or injection) drop by drop

Other synonyms of instillation include instilment.

instillation (noun)	instillment (noun)
the introduction of a liquid (by pouring or injection) drop by drop	the introduction of a liquid (by pouring or injection) drop by drop
a liquid that is instilled drop by drop