結

Mathematics

simply-connected

Computing

outer join (e.g. in relational database); left outer join

external coupling; external linkage

Physics

strong coupling

same-sex marriage; gay marriage

consolidated subsidiary

decorative knot

same-sex marriage; gay marriage

mouth shaped like a kana "he" character; mouth turned down at the corners

Shinto

Kagutsuchi; fire deity who burned to death his mother Izanami during childbirth (and was therefore beheaded by his father Izanagi)

peptide bond

Computing

tight coupling

Sumo

hairdressing of a wrestler's top-knot

unsaturated bond

(crystal) whisker

evening hairdo

var. of knot often used to tie mizu-hiki

woman's hairstyle, braided in this fashion

cryosurgery

cryotherapy

group wedding

uncoupling (usu. cars or wagons from a train)

beginning and end

to conclude one's speech

quasicrystal; paracrystal

Medicine

surgeon's knot