- i.e., i.e., that is
- imberbe, imberbate
- imbricado, imbricated
- imparipinnado, imparipinnate, odd-pinnate
- imperfecto, imperfect, unisexual
- implicado, implicate
- incano, incanous
- inciso, incised
- inclinado, cernous, drooping, inclinate
- incluido, included
- incoloro, colorless
- incompleto, incomplete
- inconspicuamente, obscurely
- íncubo, incubous
- incumbente, incumbent
- incurvado, incurved
- indehiscente, indehiscent
- indeterminado, indeterminate
- indistinto, indistinct
- indumento, vestiture, indumentum
- induplicado, induplicate
- indusio, indusium
- inequilátero, inequilateral
- inerme, inermous, unarmed
- inferior, inferior
- ínfero, inferior (applied to ovary)
- inflado, inflated
- inflexo, inflexed
- inflorescencia, inflorescence
- inflorescencia simpódica, sympodial inflorescence
- inflorescencia verticilada, verticillate inflorescence
- infra-, infr-, infra-
- infracto, infracted
- infrafoliar, infrafoliar
- infrapeciolar, infrapetiolar
- infrutescencia, infructescence
- infundibuliforme, funnel-shaped, funnelform, infundibular, infundibuliform
- inmerso, submerged
- innato, innate
- insectívoro, insectivorous
- insertado, inserted
- inserto, inserted
- insular, insular
- integumento, integument
- intenso, deep (color)
- inter-, inter-
- intercalar, intercalary
- interestaminal, interstaminal
- interfoliar, interfoliar
- interior, interior
- interno, inner, internal
- internodal, internodal
- interpeciolar, interpetiolar
- interrumpido, intermittent, interrupted
- intersticial, interstitial
- intrafoliar, intrafoliar
- intramarginal, intramarginal
- intrapeciolar, intrapetiolar
- intravaginal, intravaginal
- introducido, introduced
- introrso, introrse
- invaginación, invagination
- inverso, inversed
- invertido, inverted
- involucelo, involucel
- involucral, involucral
- involucro, involucre
- involuto, involute
- isadelfo, isadelphous
- Isla del Coco, Cocos Island (Costa Rica)
- isocárpico, isocarpic
- isocíclico, isocyclic
- isocotiledóneo, isocotylous
- isocótilo, isocotylous
- isodínamo, isodynamous
- isofilo, isophyllous
- isolateral, isolateral
- isómero, isomerous
- isopétalo, isopetalous
- isostémono, isostemonous
- iteróparo, iteroparous