tzom

Is there a connection between tzom צום - "a fast" and tzama צמא - "thirst"? Klein makes no connection between the two, yet he does not provide etymologies for either - only related words in Semitic languages. Steinberg, however, makes an interesting case for a two letter base root - צמ - that creates many words with similar meanings. They all appear to be related to the sense of "to draw together, to bind together, to contract". We find:

• צום - to fast. Steinberg describes fasting as "wrapping oneself in hunger, abstaining from eating food", as in Tehilim 107:5. Jastrow offers "to restrain one's self."
  
• צמא - to be thirsty. The tongue and throat contract from lack of water.
  
• צמד - to join, couple. Klein here says that the meaning is "he bound up, bound together". From here we get the words tzemed צמד - pair, and tzamid צמיד - bracelet, which according to Klein means "that which is bound on the wrist."
  
• צמה - lock or braid of hair, also a veil. The hair is drawn together.
• צמצם - to press, reduce, contract. From here, according to Klein, Rashi coined the word tzimtzum צמצום - restriction, limitation, which was later adopted by the Kabbalah.
• צמק - to shrink, shrivel. Raisins in Hebrew are צימוקים tzimukim.
  
• צמת - one meaning is "to join, attach, contract". From here the word tzomet צומת - juncture. Another meaning is "to oppress, subdue, destroy". Steinberg associates the pressure with the sense of contraction we see in other words with this root.
• צמח - to grow, to sprout. Steinberg connects this meaning as well, although I fail to see how. His only explanation is the somewhat cryptic comment: מיסוד צם - צמוק והתגשם