Timid describes someone who is easily frightened and has very little confidence — the child who will not put a hand up in class, the person who stands at the edge of a party. It is a quiet, inward kind of fear: not screaming-scared, but shrinking-back-scared. You can use it about a person's whole character ('a timid boy'), and also about one action ('a timid knock at the door', 'a timid smile'), which means the action was small, soft, and unsure. There is a second, very common use in business and news writing: a timid plan, a timid response, a timid government. Here it means too careful, not brave enough to do what the situation needs — and it is a criticism. Reporters like it because it is a polite-sounding way to call someone a coward. About people, timid is gentler than 'cowardly', which is an insult, but it is not a compliment either; it suggests the person is being held back by fear. If you want to say the same idea kindly, English speakers usually reach for 'shy' instead. Shy is about people and social situations, and it is neutral — many people cheerfully call themselves shy. Almost nobody calls themselves timid. The other close word is 'nervous', but nervous is a feeling right now ('I'm nervous about the test'), while timid is more often what someone is like in general.