IPA: /ˌsæŋk.tɪˈmoʊ.ni.əs.li/
KK: /sæŋkˈtɪməˌnəsli/
In a way that shows you feel morally superior to others, often in a hypocritical manner.
She spoke sanctimoniously about the importance of honesty, even though she had lied herself.
Sanctimoniously → It is formed from "sanctus" (meaning holy) and "-mony" (from Latin "monia", meaning condition or quality) combined with the adverbial suffix "-ously" (meaning in a manner). The word describes behaving in a manner that is hypocritically holy or pious.
Think of 'holy' ('sanctus') and the 'condition' of being pious ('-mony') to remember that 'sanctimoniously' means acting in a hypocritically holy way.