Feeler

n.	1.	One who, or that which, feels.
	2.	(Zool.) One of the sense organs or certain animals (as insects), which are used in testing objects by touch and in searching for food; an antenna; a palp. Insects . . . perpetually feeling and searching before them with their feelers or antennæ. - Derham.
	3.	Anything, as a proposal, observation, etc., put forth or thrown out in order to ascertain the views of others; something tentative.

Noun	1.	feeler - one of a pair of mobile appendages on the head of e.g. insects and crustaceans; typically sensitive to touch and taste Synonyms: antenna
	2.	feeler - a tentative suggestion designed to elicit the reactions of others; "she rejected his advances" Synonyms: advance, overture, approach
	3.	feeler - sensitivity similar to that of a receptor organ; "he had a special antenna for public relations" Synonyms: antenna
	4.	feeler - slender tactile process on the jaws of a fish Synonyms: barbel

advance, antenna, approach, asking price, barb, barbel, barbule, barometer, bid, bone of contention, cat whisker, catechism, cross-interrogatory, cross-question, debating point, demand, foretaste, hint, inquiry, interrogation, interrogative, interrogatory, invitation, issue, kiteflying, leader, leading, leading question, moot point, offer, offering, overture, palp, palpus, pilot balloon, point at issue, point in question, preliminary approach, presentation, probe, problem, proffer, query, question, question at issue, question mark, quodlibet, random sample, sample, sensor, sound, sounder, straw vote, submission, suggestion, tactile cell, tactile corpuscle, tactile hair, tactile organ, tactile process, tactor, tentative approach, test, tester, topic, trial balloon, vexed question, vibrissa, weather vane, weathercock