substantial, real (true, actual) · essential (necessary)
çekim: karşılaştırma ουσιαστικότερος · üstünlük ουσιαστικότερος
köken: ουσία (ousía, “essence, substance”) + -τικός (-tikós), calque of French substantiel. First attested 1890. There is a single attestation in a Koine Greek document for οὐσιαστικός (ousiastikós) but its meaning is unknown and it is not related to the current word.
essential, substantial, integral, important · material
çekim: karşılaştırma oleellisempi · üstünlük oleellisin
eş: olennainen
zıt: epäoleellinen, epäolennainen
köken: ole- + -llinen. The long -ee- is irregular, showing analogical effects of other derived words such as hyveellinen, kiireellinen, oikeellinen and tarpeellinen.