Saidin (pronounced: sah-ih-DEEN) is the male half of the One Power. It is described as a raging torrent of the Power which must be subdued and dominated by a strong-willed channeler in order to be controlled.
Men feel women holding the Source as a tingling on their skin, like goosebumps. They can also sense when another man is holding the Power though not in the way women do: a man would describe it as a feeling of awe and menace, with nothing truly visible, and not easily pinpointed to a particular location or person. The farther the channeling, the fainter the feel.
While a female channeler can sense any woman channeling, sensing for men depends largely on the amount of saidin used in the weave. No man can tell at sight if another man can channel, unless the other man has seized saidin.  So unlike women, men cannot immediately tell if another man is able to channel and cannot see when another is holding the Power, though they can feel it as a sense of menacing power, and can judge how much is being held. In order to test if a man can learn to channel, they form a simple weave as a little flame dancing in mid-air between them. The applicant concentrates on the flame and if the candidate can learn, a resonance is felt.
Saidin is described as a rough torrent that resists any attempts to control it. To employ it requires strict control, forcing it to do what you want. Male channellers universally refer to gaining the Power as "seizing" it and weaving saidin as "wielding" it like a weapon.
This essential difference in the nature of the two halves of the Power means that a woman cannot teach a man to channel, and vice versa.
Saidin strength ranking
In bold it is signed the position given by "The Wheel of Time Companion", the other positions are supposed by the description given in the books.
|Rank||Asha'man||Forsaken and Dreadlords|
|++1||Rand al'Thor||Ishamael (Moridin), Rahvin|
|++2||Logain Ablar||Aginor (Osan'gar/Dashiva), Demandred, Sammael|
|++3||-||Balthamel (Aran'gar/Halima), Asmodean, M'Hael|
|++5||Donalo Sandomere||Charl Gedwyn, Manel Rochaid|
|++6||Damer Flinn||Atal Mishraile, Welyn Kajima|
|7(1+12)||Deepe Bhadar, Naeff||Nensen|
|10(4+9)||Fedwin Morr||Peral Torval, Raefar Kisman|
|11(5+8)||Arel Malevin, Fager Neald||-|
|12(6+7)||Antail, Eben Hopwil||-|
|17(11+2)||Arlen Nalaam, Hardlin, Norley||-|
Groups/people that channel saidin
- Male Ayyad
- Samma N'Sei
- Male Forsaken
- Some False Dragons
- The Dragon Reborn
- Male Aes Sedai