Had Better for Would Better. This is not defensible as an idiom, as those who always used it before their attention was directed to it take the trouble to point out. It comes of such contractions as he'd for he would, I'd for I would. These clipped words are erroneously restored as "he had," "I had." So we have such monstrosities as "He had better beware," "I had better go."
Hail for Come. "He hails from Chicago." This is sea speech, and comes from the custom of hailing passing ships. It will not do for serious discourse.
Have Got for Have. "I have got a good horse" directs attention rather to the act of getting than to the state of having, and represents the capture as recently completed.
Head over Heels. A transposition of words hardly less surprising than (to the person most concerned) the mischance that it fails to describe. What is meant is heels over head.
Healthy for Wholesome. "A healthy climate." "A healthy occupation." Only a living thing can be healthy.
Helpmeet for Helpmate. In Genesis Adam's wife is called "an help meet for him," that is, fit for him. The ridiculous word appears to have had no other origin.
Hereafter for Henceforth. Hereafter means at some time in the future; henceforth, always in the future. The penitent who promises to be good hereafter commits himself to the performance of a single good act, not to a course of good conduct.
Honeymoon. Moon here means month, so it is incorrect to say, "a week's honeymoon," or, "Their honeymoon lasted a year."
Horseflesh for Horses. A singularly senseless and disagreeable word which, when used, as it commonly is, with reference to hippophilism, savors rather more of the spit than of the spirit.
Humans as a Noun. We have no single word having the general yet limited meaning that this is sometimes used to express--a meaning corresponding to that of the word animals, as the word men would if it included women and children. But there is time enough to use two words.
Hung for Hanged. A bell, or a curtain, is hung, but a man is hanged. Hung is the junior form of the participle, and is now used for everything but man. Perhaps it is our reverence for the custom of hanging men that sacredly preserves the elder form--as some, even, of the most zealous American spelling reformers still respect the u in Saviour.
Hurry for Haste and Hasten. To hurry is to hasten in a more or less disorderly manner. Hurry is misused, also, in another sense: "There is no hurry"--meaning, There is no reason for haste.
Hurt for Harm. "It does no hurt." To be hurt is to feel pain, but one may be harmed without knowing it. To spank a child, or flout a fool, hurts without harming.