From Hyde Flippo,
Your Guide to German Language.

Knoten: Getting Tied Up in Knots - in German
German Expressions with 'Knoten'

German Idioms and Expressions

English also has many "knot" expressions, but the German versions often mean something different from the English. There are also the usual differences between American and British usage. The British expression "tie a knot in your handkerchef" is the same as the German einen Knoten ins Taschentuch machen, but Americans "tie a string around their fingers" to remind them of something. While a "Gordian knot" is the same in German (ein Gordischer Knoten), because it is named for an ancient Greek king, "tying the knot" in German is usually expressed simply as heiraten (to get married).

Even without being used in an idiom, the English word "knot" has more meanings than you probably ever realized:

knot = string or rope tied together
knot = a bond or union; marriage (der Bund; see "tie the knot" below)
knot = lump, knob (der Knoten, die Verdickung)
knot = hair bun (der Haarknoten)
knot = an interlacement of flexible parts
knot = a cluster of persons or things (der Knäuel)
knot = junction, node (der Knotenpunkt)
knot = a tight constriction
knot = something hard to solve (ein Gordischer Knoten)
knot = one nautical mile per hour (der Knoten)
knot = a darker, dense section in a piece of lumber (der Ast)
knot = sandpiper-like bird (Tringa canutus) in the snipe family, also called robin snipe, gray snipe, or red-breasted ash-colored sandpiper

This great variety of meanings is the reason there are many ways to express "knot" in German.

Below you'll find a glossary of German and English "knot" words, plus expressions that use "knot" or "Knoten" - with example sentences and explanations where needed.
English "knot" Expressions and Idioms in German

• knot (in rope, string)
  der Knoten
  Web > ScoutNet.de - Knoten & Bünde
• knot (in wood)
  der Ast, der Knorren, die Verwachsung
• knot (verb)
  einen Knoten machen, verknoten
• knot (verb, stomach)
  sich verkrampfen
• knot (speed, one nautical mile per hour)
  der Knoten
  (We're doing / making ten knots. Wir machen zehn Knoten.)
• knot of tourists
  der Touristenknäuel
• knothole
  das Astloch
• knot together
  verknoten
• knotty (knotty pine), gnarled
  knotig, knorrig
• knotty (knotty problem, complicated)
  verwickelt, verzwickt
• (the / a) Gordian knot (a difficult problem)
  der Gordische Knoten
  ein Gordischer Knoten
• cut the Gordian knot (solve a difficult problem)
  den gordischen Knoten durchhauen / lösen
• Get knotted! (Br) - Kiss my ***! (Am)
  Rutsch mir den Buckel runter! (vulg.)
• granny knot
  der Altweiberknoten
• stomach tied up in knots
  (My stomach was all tied up in knots. Mein Magen krampfte sich zusammen.)
• tie a string around your finger (Am), tie a knot in your handkerchief (Br)
  sich (D) einen Knoten ins Handtuch machen (as a reminder)
  Note: The British expression is the same as the German.
• tie the knot (get married)
  heiraten
  (elevated, formal) den Bund der Ehe eingehen
  (elevated, formal) den Bund fürs Leben einschließen
• tie oneself (up) in knots / in a knot
  in Verwirrung geraten; sich (immer tiefer) verstricken
• tie sb (up) in knots / in a knot
  jdn in Verwirrung bringen, jdn völlig verwirren
• Windsor knot (tie)
  der Windsorknoten
  Web > Krawattenknoten (Wikipedia.de)