I'm looking for a word or a term that describes a human who actually can't think. More specifically I'm thinking of a word that describes how embryos don't feel anything or think, etc. Thanks.

For instance:

An embryo hasn't developed _________. An embryo is ________.

  • Welcome to ELU, Victor. I am not sure whether you have looked at ELU's expectations for questions. Any question needs to show what steps have been taken to find out the answer to their own question and to set the question in some sort of context, so that any of us can see the point or purpose of knowing the answer. For example, I might suggest in reply that the word for someone who can neither think nor feel anything (assuming we are talking about a living person) would be 'unconscious'. That is the only state in which the state described could be true. But what, otherwise, do you mean?
    – Tuffy
    May 17, 2019 at 13:42
  • I edited the post to include an example sentence.
    – S Conroy
    May 17, 2019 at 13:46
  • 3
    What about An embryo hasn't developed consciousness / awareness. An embryo is senseless
    – enxaneta
    May 17, 2019 at 15:40
  • 3
    @enxaneta post your answer as an answer!
    – scohe001
    May 17, 2019 at 18:27
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    Not to get in to it, but I'd suggest not using senseless due to the potential ambiguity of the word in that specific context...
    – BruceWayne
    May 17, 2019 at 19:59

3 Answers 3


An embryo hasn't yet developed sentience.

sentient condition or character; capacity for sensation or feeling.

  • 1
    Warning, this has connotations of lacking intelligence, the meaning regarding senses is secondary and not well known.
    – Ben Voigt
    May 18, 2019 at 8:09
  • @Ben Voigt. Are you sure? I've never heard or read 'sentience' used like that.
    – S Conroy
    May 18, 2019 at 12:55
  • Yes, that's one of the definitions further down in the link, the etymonline one. It doesn't say 'lacking intelligence', although if you are not capable of conscious perception then you won't be intelligent either, but nor can you be described as stupid. The label doesn't apply. At least that's how I see it.
    – S Conroy
    May 18, 2019 at 15:49
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    Sorry, I just realized what my actual object to "non-sentient" is, and it is hiding in plain sight there in the definition. An entity doesn't become sentient each morning when it wakes and non-sentient each evening when it falls asleep, sentience is an immutable property. A patient anesthetized on the operating table is still a sentient. Similarly although a human embyro doesn't think or feel, it does have the capacity/potential to do so, therefore it is sentient / has sentience.
    – Ben Voigt
    May 18, 2019 at 16:05
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    Right, it has sentient character, just not yet developed. "immature sentience" rather than non-sentient. So sentience would fit into the first blank in the question but non-sentient would not fit into the second.
    – Ben Voigt
    May 18, 2019 at 17:58

I might give "insensate" a try and see if you like it.


  1. Lacking physical sensation.

‘a patient who was permanently unconscious and insensate’

1.1 Lacking sympathy or compassion; unfeeling. ‘a positively insensate hatred’

  1. Completely lacking sense or reason. 2

‘insensate jabbering’

  • Oh, I hate this. An embryo isn't ready to do 3-D calculus -- but can we really say it doesn't have any physical sensation? May 22, 2019 at 20:30
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    @aparente001: OP states: "More specifically I'm thinking of a word that describes how embryos don't feel anything or think, etc" - I make no judgement of what they posit (this being English SE, and not a philosophy or meta-ethics SE), hence I am attempting to help OP find le mot juste - and based on the contents of OP's post, I felt this word worth their considering. May 22, 2019 at 21:13
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    From the context, I took that to refer to feeling or not feeling emotions (happy, sad, intrigued, bored, frustrated, etc.), not physical sensation. This is starting to remind me of a tedious argument I got into with a friend on a rainy day about whether cats think. // Do you think embryos lack physical sensation? I don't know what biologists think about that, actually. May 23, 2019 at 17:47

Per enxaneta's comment, both consciousness and awareness would fit. For consciousness, meanings 1 and 3 both work:

  1. the state of being conscious; awareness of one's own existence, sensations, thoughts, surroundings, etc.


  1. full activity of the mind and senses, as in waking life

Awareness carries mostly the same meaning, but has broader connotations:

the state or condition of being aware; having knowledge; consciousness

Consciousness in particular is associated with self-awareness, which may be narrower than you want. In that case, awareness (or one of the other answers here) might fit better.

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