guano /ˈɡwɑːnəʊ/noun 3verb 1forms 4 noun3 •Dung from a sea bird or from a bat.In the second experiment, a comparative trial was made between guano and bone-dust mixed with coal ashes. — 1844 •Coccothrinax borhidiana, a variety of palm tree indigenous to Cuba. •(no longer used) A variety of seabird.The Animals of these Islands, are some Hogs, Lizards, and Guanoes; and some of those Creatures mentioned in Chap. XI. which are like, but much bigger than the Guano. — 1703 verb1 •To fertilize (land) with guano. formsguanoed · guanoing · guanos · guanoes