to call together / to summon / to convene / temple or monastery (used in place names in Inner Mongolia)
召
=
刀
+
口
:
Mnemonic symbol: an intercom to call everyone together. James II of England (zh) prepares a few mandarins (口) for everyone in the aorta's bathroom (ao4) by cutting them with a cleaver (刀). As he is finished he calls everyone together (召) over the intercom (召) to come over and fetch a piece.
"speech" or "words" radical in Chinese characters (Kangxi radical 149) / see also 言字旁[yan2 zi4 pang2]
Mnemonic symbol: this character looks like a big "i" (like in information), and I'll represent it by an advertising column. Maud Younger (y) gives a speech (讠) standing on top of an advertising column (讠) in the anthill's kitchen (an2).
Characters with 诏 as component
诏
is not used as a component in another character.