Snorri explains the principles of man- and woman-kennings: a man is periphrased by his deeds, his possessions and as a 'tree' (ash, maple) of battle or ships; a woman by her attire, gold and gems, and as a feminine 'tree' (willow) or by goddesses, valkyries and norns.
Hvernig skal kenna manninn? Mann skal kenna við verk sín, þat er hann veitir eða þiggr eða gerir. Hann má ok kenna til eignar sinnar, þeirar er hann á, ok svá ef hann gaf, svá ok við ættir þær, er hann kom af, svá þær, er frá honum kómu. Hvernig skal hann kenna við þessa hluti? Svá, at kalla hann vinnanda eða fremjanda fara sinna eða athafnar, víga eða sæfara eða veiða eða vápna eða skipa. Ok fyrir því at hann er reynir vápnanna ok viðr víganna, allt eitt ok vinnandi. Viðr heitir tré. Reynir heitir ok tré. Af þessum heitum hafa skáldin kallat manninn ask eða hlyn, lund eða öðrum viðarheitum karlkenndum ok kennt til víga eða skipa eða fjár. Mann er ok rétt at kenna til allra ásaheita. Kennt er ok við jötnaheiti, ok er þat flest háð eða lastmæli. Vel þykkir kennt til álfa.
How shall a man be periphrased? A man is to be periphrased by his works — what he grants or receives or does. He may also be periphrased by the possession he owns, and likewise if he gave it away; also by the kindred he came from, and those who came from him. How shall he be periphrased by these things? Thus: by calling him doer or performer of his journeys or activity — of battles or sea-voyages or hunts or weapons or ships. And because he is the tester (reynir) of weapons and the tree (viðr) of battles — all one with 'doer'. Viðr means tree. Reynir also means tree [rowan]. From these terms the skalds have called a man ash or maple, grove, or other masculine tree-names, and periphrased him by battles or ships or wealth. It is also proper to periphrase a man by all the names of the Æsir. He is also periphrased by giant-names, and that is mostly mockery or abuse. Periphrasis by the elves is thought fitting.
Konu skal kenna til alls kvenbúnaðar, gulls ok gimsteina, öls eða víns eða annars drykkjar, þess er hon selr eða gefr, svá ok til ölgagna ok allra þeira hluta, er henni samir at vinna eða veita. Rétt er at kenna hana svá at kalla hana selju eða lág þess, er hon miðlar, en selja eða lág, þat eru tré. Fyrir því er kona kölluð til kenningar öllum kvenkenndum viðarheitum. En fyrir því er kona kennd til gimsteina eða glersteina, at þat var í forneskju kvinnabúnaðr, er kallat var steinasörvi, er þær höfðu á hálsi sér. Nú er svá fært til kenningar, at konan er nú kennd við stein ok við öll steinsheiti. Kona er ok kennd við allar ásynjur eða valkyrjur eða nornir eða dísir. Konu er ok rétt at kenna við alla athöfn sína eða við eign eða ætt.
A woman is to be periphrased by all female adornment, by gold and gems, by ale or wine or other drink that she serves or gives, and by ale-vessels and all the things it befits her to make or grant. It is proper to periphrase her by calling her the giver (selja) or 'log' (lág) of what she dispenses — and selja and lág are trees. Therefore a woman is periphrased by all feminine tree-names. And a woman is periphrased by gems or glass-stones, because in ancient times it was a women's adornment called a stone-necklace (steinasörvi) that they wore on their necks. Now it is brought to periphrasis so that a woman is periphrased by stone and by all names of stone. A woman is also periphrased by all the goddesses or valkyries or norns or dísir. It is also proper to periphrase a woman by all her activity or by possession or kindred.