1. A computer system configured to validate homonym CAPTCHAs, the computer system comprising: one or more hardware processors programmed, via executable code instructions, to implement: a CAPTCHA generator module configured to: determine a phrase of words that, when perceived together, comprises one or more meanings associated with the phrase of words that assist human perception of the phrase of words, and further comprises a homonym having a particular meaning, of multiple possible meanings for the homonym, in conjunction with use in the phrase of words; and generate a homonym CAPTCHA user interface depicting: the phrase of words including the homonym, wherein the homonym is configured for human perception as to the particular meaning of the homonym based on context of the homonym within the phrase of words, and at least two options associated with respective two or more meanings for the homonym, wherein at least one of the options is associated with the particular meaning of the homonym within the phrase of words and at least one of the options is associated with an incorrect meaning of the homonym within the phrase of words; a human validator module configured to: receive a selection of at least one of the options associated with the homonym CAPTCHA user interface; determine whether the selected option is the option associated with the particular meaning of the homonym within the phrase of words; generate an indication of whether the selected option was provided by a human based on said determination; and transmit the generated indication.