A Grammatical Dictionary of Botanical Latin

orth-, ortho-: in Gk. comp., straight, erect, upright; syn. euthy-, q.v., straight; syn. ithy-, q.v., straight; opp. campyl-, campylo-, in Gk. comp. ‘curved, bent’ (S&D); opp. plagi-, plagio-,‘oblique-;’ syn. Lat.rectus,-a,-um (adj.A), q.v.;

- orthacanthus, with straight spines; orthocarpus, with straight fruits; orthobotrys, with upright clusters; orthocladus, with straight branches; orthoclemus, with straight branchlets (Charophyta); orthoglossus, with straight tongue; orthoneurus, with straight nerves; orthopetalus, with straight petals; orthopterus, with straight or upright wings; orthosepalus, with straight sepals; orthotropus, orthotropicus, orthotropous, i.e. when the ovule has a straight axis; orthotropicus, orthotropic, with the direction of growth vertical.

Orthocarpus: from Gk. orthos, upright + karpos, fruit; “from the upright pods. Scrophulariaceae” (Stearn 1996).

Orthoceras,-atis > Gk. orthos, straight + keras, a horn; “in allusion to the appearance of the outer sepals. Orchidaceae.” (Paxton).

Orthopogon,-onis (s.m.III): > Gk. orthos, straight + pogon, a beard. Graminaceae (Paxton).

Orthosiphon,-onis (s.m.III): > Gk. orthos, straight, + siphon, a tube; “tube of the corolla straight. Lamiaceae” (Paxton).

Orthotrichum > Gk. orthos, straight + thrix, hair; “teeth of the peristome. Bryaceae” (Paxton).