| head first | Precipitately, as in diving. |
| head foremost | Precipitately, as in diving. |
| heartrending | Very depressing. |
| heathenish | Irreligious. |
| heedless | Thoughtless. |
| heifer | A young cow. |
| heinous | Odiously sinful. |
| hemorrhage | Discharge of blood from a ruptured or wounded blood-vessel. |
| hemorrhoids | pl. Tumors composed of enlarged and thickened blood-vessels, at the lower end of the rectum. |
| henchman | A servile assistant and subordinate. |
| henpeck | To worry or harass by ill temper and petty annoyances. |
| heptagon | A figure having seven sides and seven angles. |
| heptarchy | A group of seven governments. |
| herbaceous | Having the character of a herb. |
| herbarium | A collection of dried plants scientifically arranged for study. |
| herbivorous | Feeding on herbs or other vegetable matter, as animals. |
| hereditary | Passing naturally from parent to child. |
| heredity | Transmission of physical or mental qualities, diseases, etc., from parent to offspring. |
| heresy | An opinion or doctrine subversive of settled beliefs or accepted principles. |
| heretic | One who holds opinions contrary to the recognized standards or tenets of any philosophy. |
| heritage | Birthright. |
| hernia | Protrusion of any internal organ in whole or in part from its normal position. |
| hesitancy | A pausing to consider. |
| hesitant | Vacillating. |
| hesitation | Vacillation. |
| heterodox | At variance with any commonly accepted doctrine or opinion. |
| heterogeneity | Unlikeness of constituent parts. |
| heterogeneous | Consisting of dissimilar elements or ingredients of different kinds. |
| heteromorphic | Deviating from the normal form or standard type. |
| hexangular | Having six angles. |
| hexapod | Having six feet. |
| hexagon | A figure with six angles. |
| hiatus | A break or vacancy where something necessary to supply the connection is wanting. |
| hibernal | Pertaining to winter. |
| Hibernian | Pertaining to Ireland, or its people. |
| hideous | Appalling. |
| hilarious | Boisterously merry. |
| hillock | A small hill or mound. |
| hinder | To obstruct. |
| hindmost | Farthest from the front. |
| hindrance | An obstacle. |
| hirsute | Having a hairy covering. |
| hoard | To gather and store away for the sake of accumulation. |
| hoarse | Having the voice harsh or rough, as from a cold or fatigue. |
| homage | Reverential regard or worship. |
| homogeneity | Congruity of the members or elements or parts. |
| homogeneous | Made up of similar parts or elements. |
| homologous | Identical in nature, make-up, or relation. |
| homonym | A word agreeing in sound with but different in meaning from another. |
| homophone | A word agreeing in sound with but different in meaning from another. |