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submarine telegraphy

Medicine

hemorrhage in the fundus of the eye; hemorrhage in the eyeground

totally useless (fruitless) effort; wasting time on an impossible task (like trying to scoop up a reflected moon from the bottom of the sea)

Medicine

funduscopy; fundus examination; ophthalmoscopy

undersea cable (communications, power); submarine cable

base structure; underlying structure

submarine valley; submarine canyon

marine sediment

black cataract; amaurosis

pelvic floor muscle; pubococcygeal muscle; Kegel muscle

insole

perforated divider in a food steamer

mine-pit bottom

Anatomy

basal ganglia; basal nuclei

Medicine

plantar fasciitis

Colloquial

glaucoma

do your best; give it your all

valley plain

Mahjong

haitei winning hand; winning on the last tile drawn from the wall

Work of art, literature, music, etc. name

Twenty Thousand Leagues Under the Sea: A Tour of the Underwater World (1870 novel by Jules Verne)

bottom of a can

Biology

basement membrane; basal lamina

escolar (Lepidocybium flavobrunneum); snake mackerel

flat-bottomed boat; flatboat; barge; scow

base component