Definitions of feeler:

• noun:   one of a pair of mobile appendages on the head of e.g. insects and crustaceans; typically sensitive to touch and taste
• noun:   slender tactile process on the jaws of a fish
• noun:   sensitivity similar to that of a receptor organ
• noun:   a tentative suggestion designed to elicit the reactions of others
• name:  A surname (very rare: popularity rank in the U.S.: #64172)