soothe vs tranquillise

soothe and tranquillise both are verbs.

Word	Noun	Adjective	Verb	Adverb
soothe	No	No	Yes	No
tranquillise	No	No	Yes	No

As verbs, tranquillise is a hyponym of soothe; that is, tranquillise is a word with a more specific, narrower meaning than soothe:

Other hyponyms of soothe include calm, calm down, lull, quiet, quieten, still, tranquilize, tranquillize, allay, ease, relieve, still.

soothe (verb)	tranquillise (verb)
cause to feel better	cause to be calm or quiet as by administering a sedative to
give moral or emotional strength to	make calm or still