The building blocks of English

Affixes

phyco-

Seaweeds and algae.

Greek phukos, seaweed.

Phycology is the branch of botany concerned with seaweeds and other algae; a phycobilin is one of a group of red or blue photosynthetic pigments present in some algae; phycomycetes are lower fungi, so named because of their supposed resemblance to algae; a phycobiont is the algal partner in a lichen.