to assume a position, or to place (e.g. a model) in a particular position or attitude, esp for artistic purposes
to constitute (e.g. a problem or threat)
to present (e.g. a question) for attention or consideration
to assume or sustain a posture for artistic purposes
posing for the photographers
(+ as) to pretend to be somebody other than oneself
The attackers posed as insurance salesmen
Brit, informal to behave or dress in a self-consciously stylish way calculated to attract attention and impress others
[Middle English posen via early French poser from late Latin posit-, ponere to stop, rest, pause, ultimately from Latin pausa: see pause1]