compansion

As a noun compansion

is companding.

As a verb accompany is

to go with or attend as a companion or associate; to keep company with; to go along with.

As nouns the difference between compansion and companion

is that compansion is companding while companion is a friend, acquaintance, or partner; someone with whom one spends time or keeps company.

As a verb companion is

(obsolete) to be a companion to; to attend on; to accompany.

As nouns the difference between compansion and compassion

is that compansion is companding while compassion is deep awareness of the suffering of another, coupled with the wish to relieve it.

As a verb compassion is

(obsolete) to pity.

As nouns the difference between companding and compansion

is that companding is (electronics) a process in which noise in a signal is reduced by selective compression and expansion while compansion is companding.