by good luck (adverb) fortunately: luckily
Sinonime: -nouns
reciprocalness; reciprocity, reciprocation; mutuality, correlation, interdependence, connection, link, association; interchange; exchange, barter.
-verbs
reciprocate, alternate; interchange; exchange; counterchange.
-adjectives
reciprocal, mutual, commutual, correlative; alternate; interchangeable; international; complemental, complementary.
-adverbs
mutatis mutandis; vice versa; each other, one another; by turns; reciprocally.
-phrases
"happy in our mutual help" [Milton].
Antonime: sadly,
unfortunately, unhappily, unluckily