What is the meaning of Feeler?

Someone or something that feels.

An antenna or appendage used for feeling, especially on an insect.

Something ventured to test another's feelings, opinion, or position.

Someone who assumes or imagines that something said or done (positive or negative) was for the person despite having no concrete confirmation but gut feeling, one's affection is reciprocated, indulges in one's own wishful thinking, or flatters oneself

Source: wiktionary.org