May I have a word? Can I take the floor?

[englishhobby]

Is it all right to use the phrases in the title at a presentation, lecture or a similar event when the audience is supposed to ask questions to the lecturer?

[Rover_KE]

If the audience has been invited to ask questions and you have been selected after raising your hand, there's no need to say either of those; just go ahead and ask your question.

Rover

[englishhobby]

If the audience has been invited to ask questions and you have been selected after raising your hand, there's no need to say either of those; just go ahead and ask your question.

Rover

Yes, that's right, but in less formal atmosphere during various group discussions I sometimes need to say it. Would "Can I have a word?" be suitable for this type of communication?

[JMurray]

Yes, that's right, but in less formal atmosphere during various group discussions I sometimes need to say it. Would "Can I have a word?" be suitable for this type of communication?

If you are in a group discussion and want to say something to the group, you could say "Can I say something (here)?", or "I'd like to say something".
"May I have a word" is normally used when you want to say something to an individual, often in private or away from other people. Typically, you would approach the person and say "May I have a word, John?". Then both of you would move away from the group for a conversation.

not a teacher